Question 1

If the escape speed of a star is equal to the speed of light,its radius is the so-called Schwarzschild radius.What is the Schwarzschild radius of the sun,whose mass is 2.0 $\times$ 1030 kg?

Accepted Answer

A)   4.5 km
B)   1.5 km
C)   5.9 km
D)   3.0 km  D

Question 2

A 200 N box is pushed up an incline that is 5.00 m long and rises 1 m.If the incline is frictionless,then the work done by the pushing force is

Accepted Answer

A)   336 J.
B)   305 J.
C)   275 J.
D)   200 J.
E)   157 J. D

Question 3

A 120 N force is applied at an angle of 30.0 degrees above the horizontal to a 4.00 kg box.The box moves a horizontal distance of 8.00 meters.The change in the kinetic energy of the box is

Accepted Answer

A)   667 J.
B)   750 J.
C)   831 J.
D)   890 J.
E)   920 J. C

Question 4

A 2,000 kg car traveling at 30.0 mi/h skids to a stop in 60.0 meters.The force of friction during the skid is (1.0 mi/h = 0.447 m/s)

Accepted Answer

A)   4,500 N.
B)   4,200 N.
C)   3,750 N.
D)   3,000 N.
E)   2,400 N.

Question 5

A 3.00 kg pendulum bob on a string 2.00 m long is released with a velocity of 2.00 m/s when the support string makes an angle of 45.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

Accepted Answer

A)   12.5 N
B)   17.8 N
C)   21.4 N
D)   28.9 N
E)   31.6 N

Question 6

A spring-powered dart gun is un-stretched and has a spring constant 10.0 N/m.The spring is compressed by 8.00 cm and a 5.00 gram projectile is placed in the gun.The kinetic energy of the projectile when it is shot from the gun is

Accepted Answer

A)   0.020 J.
B)   0.032 J.
C)   0.060 J.
D)   0.100 J.
E)   0.120 J.

Question 7

A student lifts a weight of 10.0 N a distance of 0.500 meters.The energy needed to do this work in calories is (1 cal = 4.186 Joules)

Accepted Answer

A)   0.570 cal.
B)   0.750 cal.
C)   1.19 cal.
D)   1.75 cal.
E)   2.30 cal.

Question 8

A 90.0 kg person is running up the stairs at 0.500 m/s.The power needed to run up the stairs is

Accepted Answer

A)   441 Watts.
B)   395 Watts.
C)   302 Watts.
D)   275 Watts.
E)   257 Watts.

Question 9

A 20.0 kg box slides up a 12.0 m long incline at an angle of 30.0 degrees with the horizontal.A force of 150 N is applied to the box to pull it up the incline.The applied force makes an angle of 0.00 degrees to the incline.If the incline has a coefficient of kinetic friction of 0.100,then the increase in the kinetic energy of the box is

Accepted Answer

A)   330 J.
B)   390 J.
C)   420 J.
D)   481 J.
E)   597 J.

Question 10

The explosion in a cannon exerts an average force of 30,000 N for L meters,the length of the cannon.The length of the cannon to shoot a 2.00 kg projectile from the cannon on the earth to the moon is

Accepted Answer

A)   2.75 km.
B)   3.01 km.
C)   3.98 km.
D)   4.26 km.
E)   5.02 km.

Question 11

An airplane has a mass of 30,000 kg and travels at 300 m/s.If the drag force is 1000 N,the power the engines have to provide to keep flying at a constant speed is

Accepted Answer

A)   6.0  ×	imes×  105 W
B)   5.5  ×	imes×  105 W
C)   4.9  ×	imes×  105 W
D)   4.2  ×	imes×  105 W
E)   3.0  ×	imes×  105 W

Question 12

A 2000 kg car accelerates from rest to a velocity of 20 m/s in 10 seconds.The power of the engine during this acceleration is

Accepted Answer

A)   50 kW.
B)   40 kW.
C)   30 kW.
D)   20 kW.
E)   10 kW.

Question 13

A 20.0 kg box slides down a 12.0 m long incline at an angle of 30.0 degrees with the horizontal.A force of 50.0 N is applied to the box to try to pull it up the incline.The applied force makes an angle of 10.00 degrees to the incline and above the incline.If the incline has a coefficient of kinetic friction of 0.100,then the increase in the kinetic energy of the box is

Accepted Answer

A)   203 J.
B)   275 J.
C)   300 J.
D)   392 J.
E)   425 J.

Question 14

A 2.00 kg pendulum bob on a string 3.00 m long is released with a velocity of 1.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

Accepted Answer

A)   30.8 N
B)   27.5 N
C)   20.1 N
D)   16.6 N
E)   10.5 N

Question 15

A comet is observed to pass 1.50 $\times$ 108 m from the surface of the sun.The sun's radius is 6.96 $\times$ 108 m.What is the speed of the comet at this point,if its speed when passing the Earth's orbit,1.50 $\times$ 1011 m from the sun's center,is 25km/s?

Accepted Answer

A)   561 km/s
B)   618 km/s
C)   562 km/s
D)   585 km/s

Question 16

A spring is stretched from its equilibrium position 10 cm when a 1 kg mass is attached to it.Removing the 1 kg mass and replacing it with a 0.50 kg mass then releasing the spring,how high will the 0.50 kg mass rise above the point where it is released?

Accepted Answer

A)   0.44 m
B)   0.24 m
C)   0.80 m
D)   1.0 m

Question 17

A 20 N horizontal force is applied to a 4.0 kg box.Friction is negligible.The box moves a horizontal distance of 3.0 meters.The work done by the 20 N force is

Accepted Answer

A)   60 J.
B)   80 J.
C)   10 J.
D)   92 J.
E)   65 J.

Question 18

A 2.00 kg pendulum bob on a string 1.50 m long,is released with a velocity of 4.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the velocity of the bob at the bottom of the swing?

Accepted Answer

A)   4.47 m/s
B)   4.02 m/s
C)   3.75 m/s
D)   3.50 m/s
E)   2.85 m/s

Question 19

A dragster drives a quarter mile (402 m)at a constant rate of acceleration,starting from rest and finishing the race at a final speed of 450 km/hr.If the mass of the dragster is 975 kg,together with its driver,and rolling friction is ignored,what average power was developed by the engine,if 50% of the power developed by the engine was delivered to the wheels?

Accepted Answer

A)   4.7 MW
B)   1.2 MW
C)   0.6 MW
D)   2.4 MW

Question 20

A horizontal force is applied to a 2.0 kg box.The box starts from rest,moves a horizontal distance of 12.0 meters,and obtains a velocity of 8.0 m/s.The change in the kinetic energy is

Accepted Answer

A)   32 J.
B)   48 J.
C)   50 J.
D)   58 J.
E)   64 J.

Exam 6: Conservation of Energy

If the escape speed of a star is equal to the speed of light,its radius is the so-called Schwarzschild radius.What is the Schwarzschild radius of the sun,whose mass is 2.0 $\times$ 10³⁰ kg?

A 200 N box is pushed up an incline that is 5.00 m long and rises 1 m.If the incline is frictionless,then the work done by the pushing force is

A 120 N force is applied at an angle of 30.0 degrees above the horizontal to a 4.00 kg box.The box moves a horizontal distance of 8.00 meters.The change in the kinetic energy of the box is

A 2,000 kg car traveling at 30.0 mi/h skids to a stop in 60.0 meters.The force of friction during the skid is (1.0 mi/h = 0.447 m/s)

A 3.00 kg pendulum bob on a string 2.00 m long is released with a velocity of 2.00 m/s when the support string makes an angle of 45.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

A spring-powered dart gun is un-stretched and has a spring constant 10.0 N/m.The spring is compressed by 8.00 cm and a 5.00 gram projectile is placed in the gun.The kinetic energy of the projectile when it is shot from the gun is

A student lifts a weight of 10.0 N a distance of 0.500 meters.The energy needed to do this work in calories is (1 cal = 4.186 Joules)

A 90.0 kg person is running up the stairs at 0.500 m/s.The power needed to run up the stairs is

The explosion in a cannon exerts an average force of 30,000 N for L meters,the length of the cannon.The length of the cannon to shoot a 2.00 kg projectile from the cannon on the earth to the moon is

An airplane has a mass of 30,000 kg and travels at 300 m/s.If the drag force is 1000 N,the power the engines have to provide to keep flying at a constant speed is

A 2000 kg car accelerates from rest to a velocity of 20 m/s in 10 seconds.The power of the engine during this acceleration is

A 2.00 kg pendulum bob on a string 3.00 m long is released with a velocity of 1.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

A comet is observed to pass 1.50 $\times$ 10⁸ m from the surface of the sun.The sun's radius is 6.96 $\times$ 10⁸ m.What is the speed of the comet at this point,if its speed when passing the Earth's orbit,1.50 $\times$ 10¹¹ m from the sun's center,is 25km/s?

A spring is stretched from its equilibrium position 10 cm when a 1 kg mass is attached to it.Removing the 1 kg mass and replacing it with a 0.50 kg mass then releasing the spring,how high will the 0.50 kg mass rise above the point where it is released?

A 20 N horizontal force is applied to a 4.0 kg box.Friction is negligible.The box moves a horizontal distance of 3.0 meters.The work done by the 20 N force is

A 2.00 kg pendulum bob on a string 1.50 m long,is released with a velocity of 4.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the velocity of the bob at the bottom of the swing?

A horizontal force is applied to a 2.0 kg box.The box starts from rest,moves a horizontal distance of 12.0 meters,and obtains a velocity of 8.0 m/s.The change in the kinetic energy is

Exam 6: Conservation of Energy

If the escape speed of a star is equal to the speed of light,its radius is the so-called Schwarzschild radius.What is the Schwarzschild radius of the sun,whose mass is 2.0 ×\times× 1030 kg?

A 200 N box is pushed up an incline that is 5.00 m long and rises 1 m.If the incline is frictionless,then the work done by the pushing force is

A 120 N force is applied at an angle of 30.0 degrees above the horizontal to a 4.00 kg box.The box moves a horizontal distance of 8.00 meters.The change in the kinetic energy of the box is

A 2,000 kg car traveling at 30.0 mi/h skids to a stop in 60.0 meters.The force of friction during the skid is (1.0 mi/h = 0.447 m/s)

A 3.00 kg pendulum bob on a string 2.00 m long is released with a velocity of 2.00 m/s when the support string makes an angle of 45.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

A spring-powered dart gun is un-stretched and has a spring constant 10.0 N/m.The spring is compressed by 8.00 cm and a 5.00 gram projectile is placed in the gun.The kinetic energy of the projectile when it is shot from the gun is

A student lifts a weight of 10.0 N a distance of 0.500 meters.The energy needed to do this work in calories is (1 cal = 4.186 Joules)

A 90.0 kg person is running up the stairs at 0.500 m/s.The power needed to run up the stairs is

The explosion in a cannon exerts an average force of 30,000 N for L meters,the length of the cannon.The length of the cannon to shoot a 2.00 kg projectile from the cannon on the earth to the moon is

An airplane has a mass of 30,000 kg and travels at 300 m/s.If the drag force is 1000 N,the power the engines have to provide to keep flying at a constant speed is

A 2000 kg car accelerates from rest to a velocity of 20 m/s in 10 seconds.The power of the engine during this acceleration is

A 2.00 kg pendulum bob on a string 3.00 m long is released with a velocity of 1.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the tension in the string at the highest point of its motion?

A comet is observed to pass 1.50 ×\times× 108 m from the surface of the sun.The sun's radius is 6.96 ×\times× 108 m.What is the speed of the comet at this point,if its speed when passing the Earth's orbit,1.50 ×\times× 1011 m from the sun's center,is 25km/s?

A spring is stretched from its equilibrium position 10 cm when a 1 kg mass is attached to it.Removing the 1 kg mass and replacing it with a 0.50 kg mass then releasing the spring,how high will the 0.50 kg mass rise above the point where it is released?

A 20 N horizontal force is applied to a 4.0 kg box.Friction is negligible.The box moves a horizontal distance of 3.0 meters.The work done by the 20 N force is

A 2.00 kg pendulum bob on a string 1.50 m long,is released with a velocity of 4.00 m/s when the support string makes an angle of 30.0 degrees with the vertical.What is the velocity of the bob at the bottom of the swing?

A horizontal force is applied to a 2.0 kg box.The box starts from rest,moves a horizontal distance of 12.0 meters,and obtains a velocity of 8.0 m/s.The change in the kinetic energy is

If the escape speed of a star is equal to the speed of light,its radius is the so-called Schwarzschild radius.What is the Schwarzschild radius of the sun,whose mass is 2.0 $\times$ 10³⁰ kg?

A comet is observed to pass 1.50 $\times$ 10⁸ m from the surface of the sun.The sun's radius is 6.96 $\times$ 10⁸ m.What is the speed of the comet at this point,if its speed when passing the Earth's orbit,1.50 $\times$ 10¹¹ m from the sun's center,is 25km/s?