PHSC 103 Exam 1

A 2 kg mass has 40 J of gravitational potential energy with respect to the ground. How far is it located above the ground?

2 meters

A girl pulls on a 10 kg wagon with a constant force of 30 N. What is the acceleration of the wagon in meters per second every second?

3 m/s/s (meters per second, per second)

A block is pushed a distance of 2 meters with a force of 20 N that is in the same direction as the motion of the block. How much work is done on the block?

40 J (joules)

How much work is required to stop a 1000 kg car traveling at 10 m/s?

50,000 joules

When a woman is standing at rest with both feet on one scale, the scale reads 500 N. When she lifts one foot slightly in the air, the scale reads

500 N (newtons)

A boat loaded with pieces of scrap iron floats in a swimming pool. If the iron was thrown overboard into the swimming pool, the water level of the pool would

Fall

An Earth satellite is traveling in an elliptical orbit. It travels slowest when it is

Farthest from the Earth

If an object has no acceleration, then we can say for certain that it is

Moving at constant non-zero velocity

When an object falling in air reaches its terminal velocity, it continues to gain

Neither speed nor acceleration

As an object falls freely, its

Velocity increases

The force of friction always acts in a direction

Which opposes motion

An object travels 8 meters in it's first second of travel, 8 m again in its second second of travel and 8 m again during it's third second of travel. Its acceleration is

Zero

What is the acceleration of a car which maintains a constant velocity of 100 km/hr for 10 seconds?

Zero

If the mass of an object were to double while its volume remained the same, it's density would

double

It would be easiest to pull the two halves of the evacuated Madeborg sphere apart if they were

in a vacuum

The space shuttle orbits at altitudes greater than 200 km so as to be above the Earth's

Atmosphere

Assuming that the balls are of equal mass and the tracks are of equal length, which ball will get to the end of the track first?

Ball B

A skydiver jumps from a high flying plane. As her velocity of fall increases, her acceleration

Decreases

A ball is thrown upward with a speed of 20 m/s. What is its speed 3 seconds later?

10 m/s

A 10 kg brick and a 1 kg book are dropped in a vacuum. The force of gravity on the 10 kg brick is

10 times greater than the force on the book

A 10 ton ship is floating in the ocean. How much water will it displace?

10 tons

The roller coaster has a PE of 10,000 J when it begins its downhill run. How much total energy does it have when it is halfway down the hill?

10,000 Joules

A rock attached to a spring scale is lowered into a container of water. The scale reads 9 N and the rock has displaced 2 N of water. What is the true weight of the rock?

11 N

A car accelerates from rest at a rate of 2 m/s/s. What is its speed 6 seconds later?

12 m/s

Joey has a mass of 50 kg and he is standing at rest on the friction-less ice. His partner tosses him a ball with a mass of 10 kg and a speed of 6 m/s. Joey catches the ball firmly and he slides backward on the ice with a speed of

1 m/s

Jocko the weightlifter raised the 800 N iron block to a height of 2 meters. Fred the physics major built a 4 meter ramp so he could slide the iron block up to the same height. How much work will Fred do to slide the block up his ramp?

1,600 joules

Fluid pressure would be the greatest 3 meters below the surface of

-Lake Michigan -Your swimming pool ANSWER (-The same for both)

If you submerge 1 cubic centimeter of lead and 1 cubic centimeter of wood, the buoyant force would be greatest

-on the wood -on the lead ANSWER (-the buoyant force would be the same for both

Joe, a carpenter with a weight of 600 N, is working on a scaffold. His young son Jack is helping him. Jack has a weight of 450 N. The scaffold is held up by two ropes. One rope has an upward tension of 750 N. The weight of the scaffold is 400 N. What is the upward tension in the other rope?

700 N

A weight of 800 N is suspended at a height of 6 meters above the ground. Julia, an acrobat weighing 600N, is standing on the lower side of the see saw. There is a trapeze hanging from the ceiling some height above her. When the weight is dropped on the empty side of the seesaw, Julia will be propelled upward and she will grab onto the trapeze. What is the minimum height of the trapeze above the ground?

8 meters

If a freely falling object were equipped with a speedometer, each second its speed reading would

Increase by 10 m/s

When a falling object has reached its terminal velocity, its acceleration

Is zero

What does an object have when moving that it does not have at rest?

Momentum

A light woman and a heavy man jump from the airplane and open their same size parachutes at the same time. Who will reach the ground first?

The heavier man

The reason that the moon does not crash into the Earth is that

The moon has sufficient forward speed

An object weighs 30 N on Earth. A second object weighs 30 N on the moon. Which has the greater mass?

The object on the moon

A heavy object and a light object fall from the same height in a vacuum. They have equal

acceleration

A precious metal is sold by its weight. A supplier wants to make a profit by buying metal at one altitude and selling it at another. He should

buy at a high altitude and sell at a lower altitude

A kilogram is a measure of an object's

mass

A car traveling at 100 km/hr strikes an unfortunate bug. The acceleration is greatest on

the bug