TECHNOLOGICAL INSTITUTE OF THE PHILIPPINES PHYSICS COMPETENCY EXAM NAME_____________________STUDENT NO._________ DIRECTIONS: PROVIDE THE COMPLETE SOLUTION TO THE PROBLEMS. 1.
A car travels 100 miles to city A in 2 hours, and then travels 200 miles to city B in 3 hours. What is the average speed of the car for the trip? A. 45 mph C. 60 mph
B. 80 mph D. NOTG The position of a particle moving along the x-axis is given by x(t) = t2-t+8, where x is in units of feet, and t is in seconds. Find the velocity of the particle when t is 5 seconds. A. 9 ft/sec C. 5 ft/sec B. 11 ft/sec D. NOTG 3. If a particle’s position is given by the expression x(t) = 3.4t3-5.4t meters, what is the acceleration of the particle after 5 second? A. 65 m/s2 C. 60 m/s2 2 B. 102 m/s D. NOTG 4. A car starts from rest and moves with a constant acceleration of 6 m/s2. What is the speed of the car after 4 seconds? A. 24 m/s C. 35 m/s B. 30 m/s D. NOTG 5. A car starts from rest and has a constant acceleration of 3ft/s2. What is the average velocity during the first 10 seconds of motion? A. 30 ft/s C. 15 ft/s B. 20 ft/s D. NOTG 6. A truck increases its speed uniformly from 13km/hr to 50 km/hr in 25 seconds. What is the acceleration of the truck? A. 0.536 m/s2 C. 0.156 m/s2 2 B. 0.411 m/s D. NOTG 7. A bicycle moves with a constant deceleration of 2ft/s2. If the initial velocity of the bike was 10 ft/s, how far does it travel in 3 seconds? A. 35 ft C. 53 ft B. 21 ft D. NOTG 8. A ball is dropped from a height of 60 meters above the ground. How long does it take to hit the ground? A. 2.5 sec C. 3.5 sec B. 1.5 sec D. NOTG 9. A man driving a car at 45 mph suddenly sees an object in the road 60 feet ahead. What constant deceleration is required to stop the car in this distance? A. 43.3 ft/s2 C. 36.3 ft/s2 2 B. 23.2 ft/s D. NOTG 10. A ball is thrown vertically upward with an initial speed of 80 ft/sec. How long will it take for the ball to return to the thrower? A. 4.97 sec C. 1.36 sec B. 10.56 sec D. NOTG 2.
11. A projectile is launched upward from level ground at an angle of 60° with the horizontal. It has an initial velocity of 45 m/s. How long will it take before the projectile hits the ground? A. 7.94 s C. 10.3 s B. 5.36 s D. NOTG 12. A man standing at a window 5 meters tall watches a falling ball pass by the window in 0.3 seconds. From how high above the top of the window was the ball released? A. 11.8 m C. 30.36 m B. 20.6 m D. NOTG 13. A car starting from rest moves with a constant acceleration of 10 mi/hr2 for 1 hour, then decelerates at a constant 5 mi/hr2 until it comes to a stop. How far has it travelled? A. 20 mi C. 15 mi B. 30 mi D. NOTG 14. A stream flows at 3 mph. At what angle upstream should a boat travelling at 8 mph be launched in order to reach the shore directly opposite to the launch point? A. 4° C. 10° B. 22° D. NOTG 15. A 3 kg block is moving at a speed of 5m/s. What is the force required to bring the block to a stop in 0.0008 seconds? A. 54 kN C. 18.8 kN B. 4.4 kN D. NOTG 16. An object is launched at 45 to the horizontal on level ground. What is the range of the projectile if its initial velocity is 180 ft/sec? A. 1000 ft C. 117.35 ft B. 45.60 ft D. NOTG 17. A projectile leaves a velocity of 50 m/s at an angle of 30° with the horizontal. Find the maximum height that it could reach? A. 31.86 m C. 17.26 m B. 25.90 m D. NOTG 18. A plane dropped a bomb at an elevation of 1000 meters from the ground intended to hit the target at an elevation of 200 meters from the ground. if the plane was flying at a velocity of 300 km/hr, at what distance from the target must the bomb be dropped to it the target? A. 2100.5 m C. 3153.8 m B. 1064.2 m D. NOTG 19. A car of mass 1000 slugs accelerates in 10 seconds from rest at a constant rate to a speed of 20 ft/sec. What is the resultant force on the car due to this acceleration? A. 1000 lbf C. 3000 lbf B. 2000 lbf D. NOTG 20. A ball is dropped onto a solid floor from an initial height, h0. If the coefficient of restitution is 0.90, how high will the ball rebound? A. 0.81h0 C. 0.45h0 B. 1.80h0 D. NOTG 21. A 16 grams mass is moving at 30cm/s while a 4 gram mass is moving in an opposite direction at 50 cm/s. they collide head on and stick together. their velocity after collision is
A. 0.14 cm/s C. 0.45 cm/s B. 0.28 cm/s D. NOTG 22. A 60 ton rail car moving at 1 mi/hr is instantaneously coupled to a stationary 40 ton rail car. What is the speed of the coupled car? A. 0.9 mph C. 0.6 mph B. 0.1 mph D. NOTG
23. A 10 g block slides with a velocity of 20 cm/s on a smooth level surface and makes a collision with a 30g block moving in the opposite direction with a velocity of 10 cm/s. if the collision is perfectly elastic, what is the velocity of the 30 g block after the collision? A. 10 cm/s C. 30 cm/s B. 5 cm/s D. NOTG 24. A 60 ton rail car moving at 1 mi/hr is coupled to a second stationary car. if the velocity of the two cars after coupling is 1 ft/s and the coupling is completed in 0.5 second, what is the average impulsive force on the 60 ton rail car? A. 3478.51 lbf C. 2648.35 lbf B. 9863.32 lbf D. NOTG 25. The voltage drop across a device is 50 volts, and the current drawn is 30 A. The power rating of this device is? A. 1 h C. 5.02 hp B. 2.01 hp D. NOTG 26. A charge of 0.75 coulombs passes through a wire every 15 seconds. What is the current in the wire? A. 0.05 A C. 11.25 A B. 0.03 A D. NOTG 27. What is the speed of light through a glass whose index of refraction is 1.33? A. 3.11x108 m/s C. 2.26x108 m/s 8 B. 1.29x10 m/s D. NOTG 28. What is the index of refraction of a material if the speed of light through the material is 2.37x108 m/s? A. 1.35 C. 1.27 B. 1.56 D. NOTG 29. An object 6 centimeters high is placed 12 centimeters away from a concave mirror whose focal length is 36 centimeters. What is the height of the image? A. 5 cm C. 9 cm B. 3 cm D. NOTG 30. A magnifying glass has a plastic lens with an index of refraction of 5.4 and radii of curvature of 2.95 feet and 4.27 feet for the two faces. What is the magnification of the lens when it is held 2.36 inches from an object being viewed? A. 1.98 C. 1.12 B. 1.53 D. NOTG 31. What is the photon energy associated with green-blue light of wavelength 500 nanometers? A. 2x10-19 J C. 4x10-19 J -19 B. 6x10 J D. NOTG
32. A stationary observer hears a siren approaching. the siren has a sound frequency of 700 Hz, and is approaching the observer at 50 mph. what is the frequency heard by the observer? assume the velocity of sound of air is 1087 ft/sec. A. 120 Hz C. 512 Hz B. 750 Hz D. NOTG 33. Three forces 20, 30, 40 N respectively are in equilibrium. Find the largest angle they make with each other? A. 104.48° C. 234.48° B. 14.48° D. NOTG 34. Two forces of 20 unit and 30 units act at right angle. What is the magnitude of the resultant force? A. 20 units C. 36 units B. 15 units D. NOTG 35. What is the magnitude of the resultant force of the two forces 200 N at 20° and 400 at 144°? A. 350 N C. 332.5 N B. 201 N D. NOTG 36. A 100 kg weight rest on a 30° incline plane. Neglecting friction, how much pull must one exert to bring the weight up the plane? A. 50 kg C. 75 kg B. 100 kg D. NOTG 37. A block weighing 500 kN rest on a ramp inclined at 25° with the horizontal. The force tending to move the block down the ramp is A. 235 kN C. 105 kN B. 211 kN D. NOTG 38. A man exerts a maximum pull of 1000 N but wishes to lift a new stone door his cave weighing 20000 N. If he uses a lever, how much closer must the fulcrum be to the stone than to his hand? A. 10 times nearer C. 15 times nearer B. 20 times nearer D. NOTG 39. A beam rests on a fulcrum, 1.2m from one end. A weight of 350 kg is suspended from this end causing the beam to balance. If the weight of 350 kg is suspended on the opposite end of the beam, it is necessary to suspend 1000 kg weight on the first end in order to balance. Find the length of the beam. A. 2.48 m C. 3.43 m B. 2.45 m D. NOTG 40. A 40 kg block is resting on an inclined plane making an angle of 20° from the horizontal. if the coefficient of friction is 0.60, determine the force parallel to the incline that must be applied to cause impending motion down the plane. A. 87 N C. 54 N B. 23 N D. NOTG 41. A 250 lb block is initially at rest on a flat surface that is inclined at 30°. if the coefficient of kinetic friction is 0.30 and the coefficient of static friction is 0.40, find the force required to start the block moving up the plane. A. 120 lb C. 351 lb B. 212 lb D. NOTG
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A 200 lb man hangs from the middle of a tightly stretched rope so that the angle between the rope and 5 the horizontal direction is . Calculate the tension of the rope? a. 1104 lb b. 1147 lb c. 1205 lb d. 1250 lb Two men lift the ends of a 20ft beam weighing 200 lb onto their shoulder. Both men are of the same height so that the beam is carried horizontally, but one is much stronger and wishes to bear 50% more of the weight than his mate. How far from the end of the beam should he put his shoulder? a. 1.5 ft b. 2 ft c. 2.75 ft d. 3.33 ft A 20 kg child and 30 g child sit at the opposite ends od4-m seesaw that is pivoted at its center. How many meters from the 20 kg child should another 20-kg child sit in order to balance the seesaw? a. 0.5 m b. 0.75 m c. 1.0 m d. 1.25 m A door 7 ft high and 3 ft wide has hinges at the top and bottom of one edge. Each hinge supports half of the 40-lb weight of the door. Find the horizontal components of the door exerted on each hinge. a. 8.6 lb b. 9.6 lb c. 10.6 lb d. 11.6 lb An automobile traveling at a speed of 30 mph accelerates uniformly to a speed of 60 mph 10 seconds. How far does the automobile travel during the time of acceleration? a. 330 ft b. 440 ft c. 550 ft d. 660 ft During a takeoff roll, a jumbo jet is accelerating at 4m/s2. If it requires 40 s to reach takeoff speed, determine the takeoff speed? a. 160 m/s b. 180 m/s c. 200 m/s d. 220m/s The turntable of a record player is accelerated from rest to a speed of 33.3 rpm in 2 seconds. What is the angular acceleration in radian per second square? a. 1.54 b. 1.64
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c. 1.74 d. 1.84 A man standing on a roof of a building 30 m high throws a ball vertically downward with an initial velocity of 5m/s. What is the velocity of the ball as it strikes the ground? a. 20.76 m/s b. 22/76 m/s c. 24.76 m/s d. 26.76 m/s 40 A shell is fired at an angle above the horizontal at a velocity of 300 m/s. What is the time of flight? a. 39 s b. 41 s c. 43 s d. 45 s A rifle with a muzzle velocity of 200m/s is fired with its barrel horizontal at a height of 1.5 m above the ground. How far away from the rifle does the bullet strike the ground? a. 100 m b. 110 m c. 120 m d. 130 m A 60-g tennis ball approaches a racket at 15m/s,is in contact with the racket for 0.005 s, and rebounds at 20m/s.Find the average force that the racket exerted on the ball? a. –420 N b. –450 N c. –480 N d. –510N An empty truck whose mass is 2000 kg has a maximum acceleration of 1m/s2. What is the maximum acceleration be when it carries load of 1000 kg? a. 0.5m/s2 b. 0.67 m/s c. 0.75 m/s d. 1m/s2 A weight of 50 lb and another of 30lb are suspended by a rope on either side of a frictionless pulley. What is the acceleration of each weight? a.8 ft/s b. 9 ft/s2 2 c.10 ft/s d. 12 ft/ s2 A 3200lb car is slowed down uniformly from 60mphto 15 mph along a level road by a force of1100lb. How far does it travel while being slowed down? a. 330 ft b. 440 ft c. 50 ft d. 660 ft A 500 kg bucket is raised and lowered in a vertical mine shaft using a cable. Determine the upward force exerted by the cable when the upward acceleration is 4 m/2. a. 4900N b. 5900 N c. 6900 N d. 790N What is the acceleration at a point on a rim of a flywheel0.90 m in diameter, turning at a rate 120 mph a. 5700 m/s b. 6200 m/s s c. 6600 m/ d. 7100 m/s A train whose speed is60 mph rounds a curve whose radius of curvature is 484 ft. What is the acceleration in ft/s? a. 12 b. 13.5 c. 15 d. 16 What is the minimum coefficient of static friction required of a curvature car traveling at 60 kph to make a level turn 40m in radius? a. 0.65 b. 0.68 c. 0.71 d. 0.75
19. The coefficient of static friction between s car’ s fire and a certain concrete road is 0.99 when the road is dry and 0.7 when the road is wet. If the car can safely make a certain turn at 50kph an dry day, what is the maximum velocity on a rainy day? a. 35 kph b. 37.5khh c. 40 kph d. 42 kph 20. A 10-g bullet has a velocity of 600m/swhen it leaves the barrel of a riffle. If the barrel is 60 m long, find the average force on the shell while it is no barrel? a. 3000 N b. 3500 N c. 4000 N d. 4500 N 21. A rubber ball is dropped on a floor from a height of 5 m. If the coefficient of restitutions is 0.7, find the height of the which ball rebounds? a. 2.45 m b. 2.75 m c. 3.25 m d. 3.5 m 22. A 40 kg skater traveling at 4 m/s overtakes a 60 kg skater traveling at 2 m/s in the same direction and collides with him. If the two skaters remain in contact, what is their final velocity? a. 2.4 m/s b. 2.65 m/s c. 2.8 m/s d. 3 m/s 23. A 5 kg rifle fires a 15 g bullet at a muzzle velocity of 600 m/s. Find the recoil velocity of the rifle. a. –1.8 m/s b. –2.25 m/s c. –2.5 m/s d. –3 m/s 24. A 200 g of water is mixed to 300 g of alcohol whose density is 790kg/ m3. Calculate the specific gravity of the total mixture. a. 0.675 b. 0.862 c. 0.912 d. 1.0 25. A 72 kg man jumps off a raft whose base area is 4 m 2 floating in a freshwater lake. By how much does the raft rise? a. 1.8 cm b. 2.0 cm c. 2.25cm d. 2.5 cm 26. The density of ice is 920 kg/m 3 and that of seawater is 1030 kg/m3. What percentage of the volume of an iceberg is submerged? a. 11% b. 15 % c. 85 % d. 89 % 27. A steel beam in a bridge extends 25 m across a small stream. What is the change in length from the winter, 20 when the temperature is C, to the summer when 37 it is C. The coefficient of linear expansion of C -6 steel is 12x10 / . a. 17mm b. 19 mm c. 21mm d. 23 mm 20 C 28. At , an aluminum rod and a copper rod have the same lengths f 1.85m. To what temperature must they be heated to differ in length by 0.02 cm? The coefficient of linear expansion of aluminum and C C copper are is 16.8 x10-6 / and 24x10-6 , respectively.
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40 29. 5 kg of water at is poured on a block of ice at 0C . How much ice melts? a. 1 kg b. 1.5 kg c. 2 kg d. 2.5 kg 20 C 30. A total of 0.8 kg of water at is placed in 1 kW electric kettle. How long a time is needed to raise the 100 C temperature of water to . a. 3.5 min b. 4.5 min c. 5.5 min d. 6.5 min 90 C 31. In preparing a tea, 600 g of water at is poured into 200 g china pot whose specific heat capacity is C 20 C 840J/kg and temperature of . What is the final temperature of water? 81 .6C 83 .6C a. b. 85 .6C 87 .6C c. d. 0.5C 32. Two charges, one of + 0 .2 C
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, attract each other with a force of 100 N. How far apart are they? a. 3 mm b. 4 mm c. 30 mm d. 40 mm A 12 V storage battery is being charged at a rate of 15C/s. how much power is being used to charge the battery? a. 150 W b. 180 W c. 210 W d. 240 W A 100 ohm and 200 ohm resistor are connected in series with a 40 V power source. How much power is dissipated by the 100 ohm resistor? a. 1.78W b. 2.25W c. 3.28W d. 3.55W 20 A wire has a resistance of 30 ohm at C. What is 80 the resistance at C assuming that the temperature 20 coefficient of resistance is 0.00385 at C? a. 33.93 ohms b. 34.93 ohms c. 35.93 ohms d. 36.93 ohms A wire has a resistance of 5 ohms. What will be the resistance of another wire of the same material three times as long and half the cross sectional area? a. 30 ohms b. 25 ohms c. 28 ohms d. 60 ohms 25
37. A 10-ohm resistor, 2 H conductor and F capacitor are connected in series. What current will
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be drawn if the circuit is connected across a 200 V, 60 Hz supply? a. 0.15 A b. 0.23 A c. 0.31 A d. 0.47 A Five 1.5 V cells are connected in series. If the internal resistance of each cell is 0.25 ohm, what external resistance will produce a current of 2 A through the cells? a. 1.75 ohms b. 2.25 ohms c. 2.5 ohms d. 3 ohms Find the length in meters of a simple pendulum whose period is 2 seconds? a. 0.8 b. 1.0 c. 1.2 d. 1.5 A 100 g object is suspended from a spring whose force constant is 50N/m. What is its frequency? a. 3.56Hz b. 4.56 Hz c. 5.56 Hz d. 6.56 Hz How many times more intense is a 50 dB sound than a 40 dB sound? a. 1.25 b. 10 c. 100 d. 1000 Calculate the fundamental frequency of vibration of the A-string of a violin, whose mass is 0.30 g and length is 33 cm and is stretched under a tension of 77N? a. 220 Hz b. 310 Hz c. 390 Hz d. 440 Hz The siren of a fire engine has a frequency of 500 Hz. If the fire engine approaches a stationary car at 20m/s, what frequency does a person in a car hear? a. 471 Hz b. 500 Hz c. 531 Hz d. 565 Hz The siren of a stationary fire engine has frequency of 50o Hz. If a car drives away from it at 20m/s, what frequency does a person in the car hear? a. 471 Hz b. 500 Hz c. 531 Hz d. 565 Hz
45. The index of refraction of diamond is 2.42. What is the velocity of light in the diamond in m/s? a. 1.24 x 108 b. 1.24 x 108 c. 3 x 108 d. 7.28 x 108 46. A beam of light in air falls on a glass surface of an 20 angle of incidence of .If the angle of refraction in 12 .4 the glass is , what is the index of refraction of the glass? a. 1.5 b. 1.59 c. 1.66 d. 1.72 47. The water in the swimming pool is 2m deep. How deep does it appear to be someone looking down it if the index of refraction of water is 1.33? a. 1.33 m b. 1.5 m c. 1.75 m d. 2 m 48. A doughnut 3 inches in diameter is places 24 inches from a converging lens whose focal length is 16 inches. What is the size of the image? a. –4 in b. –6 in c. 3 in d. 5 in 49. A planoconcave lens has one plane surface and one concave surface. If the planoconcave lens of focal length of –10cmis to be ground from optical glass of index of reaction, find the radius of curvature of the surface. a. –5 cm b. –10 cm c. 5cm d. 10 cm 50. Glycerin has an index of reaction of 1.47. Find the focal length in glycerin of a lens made of flint glass(n= 1.63) whose focal length in air is 10 cm. a. 11 cm b. 23cm c. 39 cm d. 58
