What must happen for work to be done on an object?

A) A force must be applied and the object must move

Why does using an inclined plane make lifting easier?

C) It decreases the amount of force needed over a greater distance

A machine has a mechanical advantage greater than 1. What does this mean?

B) It decreases the force needed

Which of these is an example of work being done?

C) Lifting a book off the ground

Why can no machine be 100% efficient?

A) Energy is lost due to friction

A powerful machine does work ____.

A) Faster than a less powerful machine

studbud

Work and Power Review

11 termsStudBud Administration

Imported from external platform

Flashcards11 cardsFPractice quizPHost liveL

Questions 11

Answers

1
What must happen for work to be done on an object?
A) A force must be applied and the object must move
B) The object must change shape
C) A force must be applied for at least 10 seconds
D) The object must gain energy
2
Why does using an inclined plane make lifting easier?
A) It reduces the amount of work needed
D) It adds friction to help the movement
B) It increases the force required
C) It decreases the amount of force needed over a greater distance
3
A screwdriver is an example of which simple machine?
B) Screw
C) Wheel and axle
D) Lever
A) Wedge
4
A machine has a mechanical advantage greater than 1. What does this mean?
A) It increases the force applied
D) It requires more input work
C) It moves objects automatically
B) It decreases the force needed
5
If you apply 50N of force and move an object 4 meters, how much work do you do?
B) 200 J
D) 100 J
C) 54 J
A) 12 J
6
Which simple machine is found in a seesaw?
B) Lever
D) Screw
A) Pulley
C) Wedge
7
Which of these is an example of work being done?
C) Lifting a book off the ground
A) Pushing a car that doesn’t move
D) Sitting in a chair
B) Holding a heavy box still
8
Why can no machine be 100% efficient?
A) Energy is lost due to friction
C) Work input is always greater than output
D) Machines don’t follow the laws of physics
B) Machines gain energy from work
9
A powerful machine does work ____.
B) With less force
A) Faster than a less powerful machine
C) Without using energy
D) Only when it has a battery
10
A worker lifts a box with 30N of force over 2 meters in 3 seconds. What is their power output?
B) 20 W
C) 15 W
A) 10 W
D) 5 W
11
What simple machine is used in an axe?
B) Lever
C) Wedge
A) Wheel and axle
D) Pulley

Work and Power Review Flashcards | StudBud