Unit 4 Review

Where should the fulcrum be located in this lever to get the greatest mechanical advantage?

• At position II, because the effort arm and the load arm should have equal lengths.

• At position IV, because the effort should be applied as close to the fulcrum as possible.

• At position I, because the length of the effort arm should be greater than the length of the load arm.

• At position III, because the length of the load arm should be greater than the length of the effort arm.

Tags

NGSS.MS-ETS1-1

NGSS.MS-ETS1-2

NGSS.MS-PS2-2

What is the purpose of using a simple machine in the case described below?

• To reduce the amount of friction

• To reduce the distance the box has to travel

• To reduce the amount of work needed to lift the box

• To reduce the amount of force needed to lift the box

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-5

Calculate the amount of work done if you use a 200 N force to push a 50 kg box 5 m across the kitchen floor.

• 1000N

• 4J

• 40N

• 1000J

Tags

NGSS.MS-PS2-2

Which of the following does a simple machine do?

• allows the users to apply less force over a longer distance

• reduce the amount of force needed to do work

• change the direction of the applied force

• all of the above

You do 90 joules of work in 30 seconds. How much power have you generated?

• 30 watts

• 3 watts

• 120 watts

• 270 watts

You move a 8 N object five meters in 4 seconds. How much power have you generated?

• 160 watts

• 10 watts

• 6.4 watts

• 17 watts

Answer explanation

Work(40J) = Force(0.8N) x Distance(5m)

Power(10W) = Work(40J) / Time(4s)

What type of simple machine is found on the cap of a jar?

• Screw

• Pulley

• Lever

• Inclined Plane

What is this simple machine?

• Inclined Plane

• Lever

• Gear

• Wheel and axle

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

Which of the following is a true statement about work?

• It measures how quickly an object accelerates 

• It measures how much effort is applied over a certain distance

• It measures the change in an object's rate of speed

• It measures how much time it takes to move a massive object

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Which of these is a measure of force?

• 100 newtons

• 100 meters per second

• 100 joules

• 100 watts

Tags

NGSS.MS-PS2-2