Science
Work & Simple Machines
Grade 8 · Middle School
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- Question 1 of 20Easy
In science, work is defined as ...
- Question 2 of 20Easy
The SI unit of work is the ...
- Question 3 of 20Easy
The SI unit of power is the ...
- Question 4 of 20Easy
Which of the following is a simple machine?
- Question 5 of 20Easy
The mechanical advantage of a simple machine is the ratio of ...
- Question 6 of 20Easy
An example of using an inclined plane is ...
- Question 7 of 20Medium
A force of 50 N pushes an object 4 m in the direction of the force. The work done is ...
- Question 8 of 20Medium
A machine does 600 J of work in 3 s. Its power is ...
- Question 9 of 20Medium
Scissors are a ... lever.
- Question 10 of 20Medium
The mechanical advantage of a fixed pulley is ...
- Question 11 of 20Medium
Using an inclined plane reduces the effort force, but ...
- Question 12 of 20Medium
The mechanical advantage of a movable pulley is ...
- Question 13 of 20Medium
A person pushes a wall with all their strength, but the wall does not move. The work done by the person is ...
- Question 14 of 20Medium
A 300 N load is lifted with a lever using 100 N of effort. The lever's mechanical advantage is ...
- Question 15 of 20Hard
A 10 kg object is lifted 2 m high with g = 10 m/s^2. The work needed is ...
- Question 16 of 20Hard
A force of 200 N pushes an object 5 m in 2 s. The power used is ...
- Question 17 of 20Hard
An inclined plane 1 m high and 4 m long is used to lift an 800 N load. The minimum effort force needed is ...
- Question 18 of 20Hard
A lever has an effort arm of 2 m and a load arm of 0.5 m. If the load is 400 N, the effort force needed is ...
- Question 19 of 20Hard
A lifting device uses one fixed pulley and two movable pulleys. Its mechanical advantage is ...
- Question 20 of 20Hard
An inclined plane lifts a 500 N load 2 m high. The plane is 5 m long and the effort is 250 N. The efficiency of the plane is ...