Physics Unit 4

Question 1

Which one is stronger gravitational or electrical force?

Answer 1

Electrical

Question 2

To raise a bucket of water from a well, you could tie a rope to cylinder that can be rotated with a crank having an larger radius than that of the cylinder; in other words, you could have used a(n):

Answer 2

wheel and axle system

Question 3

The ____ of a machine or actual Mechanical Advantage is measured by dividing the useful work output by the total work input.

Answer 3

efficiency

Question 4

A tire sits atop a ramp. When the tire is released, it rolls down the ramp. According to the law of conservation of energy, KEi+PEi=KEf+PEf,
what force caused by the surfaces of the tire and ramp act against this?

Answer 4

Friction

Question 5

During a move, to reduce the work necessary to move a refrigerator from the street level to the height of the truck, the movers place the refrigerator on the moving van’s ramp leading to its interior. This ramp is an example of a(n):

Answer 5

inclined plane

Question 6

Movers transport a refrigerator with a mass of 113 kg the distance of 22 m from your kitchen to their truck. After they complete this task, the movers will have performed:

Answer 6

work

Question 7

The formula F1d1=F2d2
states that the force times the distance on one side of a lever’s fulcrum equals the force times the distance on the other side of the fulcrum, this is the:

Answer 7

Law of moments

Question 8

A tire sits atop a ramp. When the tire is released, it rolls down the ramp. As the tire rolls down the ramp its ______ increases but its
______ energy remain the same.

Answer 8

Kinetic/ mechanical

Question 9

A tire sits atop a ramp. When the tire is released, it rolls down the ramp. As the tire rolls down the ramp due to _________, the tire’s
_______energy decreases.

Answer 9

gravity/potential

Question 10

The reason to use machines to accomplish work is the:

Answer 10

mechanical advantage

Question 11

An object with a particular mass is moved due to a _____, an event that is expressed in the formula F=ma

Answer 11

force

Question 12

The scientist who wrote the law of universal gravitation was:

Answer 12

Isaac Newton

Question 13

The force that binds protons and neutrons in an atom’s nucleus together is the _____ force.

Answer 13

strong nuclear

Question 14

Another name for the fulcrum is:

Answer 14

point of rotation

Question 15

The ramp the movers use to help them move a refrigerator into the moving van modifies the force necessary to perform work and therefore is a(n) ______.

Answer 15

machine

Question 16

A tire sits atop a ramp. When the tire is released, it rolls down the ramp. At the ramp’s bottom, the speeding tire knocks down the barricade. What energy is responsible for knocking down the barricade?

Answer 16

mechanical

Question 17

An object with positive charge will _____ an object with negative charge.

Answer 17

attract

Question 18

If you use a claw hammer as a lever to pull a nail, the handle is the ____________.

Answer 18

lever

Question 19

Construction workers were raising heavy steel beams up 10 meters, unfortunately, they dropped them. As the beams fell towards the ground the energy they possessed at 10 meters above the street was converted into ______ energy.

Answer 19

kinetic

Question 20

Construction workers were moving heavy steel beams up 10 meters, unfortunately, they dropped them. The falling beams slam into a car and crush it due to their ____________ energy.

Answer 20

mechanical

Question 21

Movers transport a refrigerator with a mass of 113 kg the distance of 22 m from your kitchen to their truck. As the movers move the refrigerator up a ramp, they momentarily slip back 4 meters. The slippage results in:

Answer 21

negative work

Question 22

A short-range force inside an atom, responsible for nuclear decay that is inside an atom, the ________ force is a type of electromagnetic force.

Answer 22

weak nuclear

Question 23

The scientist who discovered that the earth and other planets rotate in elliptical orbits around the sun, that the square of the period of revolution about the sun is proportional to the cube of the average distance from the sun, and that the line joining the planet to the sun sweeps out equal areas in equal times as the planet travels around the ellipse was _____.

Answer 23

Johannes Kepler

Question 24

The total distance a group of movers move a refrigerator is 22 m. If they complete this task in 15 minutes, their efforts would be expressed in units of:

Answer 24

power

Question 25

Construction workers must move heavy steel beams up 10 meters. They opt to use a system that employs ropes draped over wheels to reduce the amount of force necessary to move the load. This is also known as a(n):

Answer 25

pulley systems

Question 26

A worker applied 27 newtons to a lever with a length of 4 meters that rotated around a hinge. What was the torque?

Answer 26

108 N * m

Question 27

The scientist who found that charges on objects were proportional according to F(electric)=k(c)q1q2/d2 was:

Answer 27

Charles-Augustin de Coulomb

Question 28

You need to insert a screw into a piece of wood. To do so, you apply _______ or a force over a distance to create circular motion in the screw.

Answer 28

torque

Question 29

The total distance a group of movers move a refrigerator is 22 m. This is the:

Answer 29

net work

Question 30

In one hour, the planet sweeps out an area near it perihelion that equals to the same area swept out near its aphelion in the same amount of time. (Area 1 = Area 2). This fact is described by _____.

Answer 30

Kepler’s Second Law

Question 31

In one hour, the planet sweeps out an area near it periphelion that equals to the same area swept out near its aphelion in the same amount of time. (Area 1 = Area 2). This law proves that the earth is traveling _____ at its perihelion than at its aphelion.

Answer 31

faster

Question 32

If you were informed that it takes one year for the earth to revolve around the sun, and that the square of that period was proportional to the cube of the earth’s average distance from the sun, what law would fit that description?

Answer 32

Kepler’s Third Law

Question 33

At point 1, Planet A is at its _____, or closest position to the sun.

Answer 33

Perihelion

Question 34

At point 2, Planet A is at its _____, or furthest position from the sun.

Answer 34

aphelion

Question 35

If planet A is the Earth, what law showed that the earth revolved around the sun?

Answer 35

Kepler’s first law