Welcome to your Grade 9 Physics chapter 5
After carefully reading the following 30 questions, choose the correct answer.
1.
What is a device that makes it easier to do mechanical work?
2.
A pulley is defined as a circular body with a:
3.
Which type of pulley is used primarily to change the direction of the force?
4.
Which pulley uses more effort than the load to lift the load when used individually?
5.
What acts as the fulcrum in a fixed pulley attached to a ceiling?
6.
What is the velocity ratio of a 12 cm long and 3 cm wide wooden wedge?
7.
Calculate the mechanical advantage of a lever that lifts 100 N load with an input force of 20 N.
8.
In every simple machine, why is AMA (Actual Mechanical Advantage) always less than IMA (Ideal Mechanical Advantage)?
9.
A block of weight 6000 N is pushed up a slope by a force of 300 N. What is the actual mechanical advantage (AMA)?
10.
How many classes of levers are there?
11.
The fixed pulley acts as which class of lever?
12.
What is the advantage of using a fixed pulley?
13.
What is the velocity ratio of a slope if its height is 10 m and the actual mechanical advantage is 20 (assuming no energy loss)?
14.
A wedge is often considered as a type of:
15.
In a simple machine, efficiency is the ratio of work output to:
16.
Which of the following is an example of a wedge?
17.
What term refers to the force applied to a simple machine?
18.
If a movable pulley is dirty and adds 5 N of friction, how much total effort is needed to move a 140 N load? (Assume Ideal VR = 2)
19.
The point about which a lever rotates is called the:
20.
Velocity ratio (V.R) is the ratio of distance moved by effort to:
21.
Which machine consists of a wheel and an axle?
22.
A screw is essentially an inclined plane wrapped around a:
23.
Mechanical advantage (AMA) is the ratio of:
24.
A second-class lever has the:
25.
Which of these is NOT a type of simple machine?
26.
The distance between the threads of a screw is called the:
27.
A ramp used to load a truck is an example of:
28.
In a third-class lever, the effort is located:
29.
What is the AMA of a machine if the load is 500 N and the effort is 100 N?
30.
The efficiency of a real machine is always:
