WorksheetsPre assessment (Simple/Compound machine, Power, Efficiency)
Total questions: 15
Worksheet time: 23mins
Which of the following is a simple machine?
Lever
Bicycle
Motor
Engine
In a first-class lever, the fulcrum is located
At one end of the lever
In the middle of the lever
At the load
Directly under the input force
Which of the following examples best illustrates a compound machine?
Scissors
Screwdriver
Pulley
Wheelbarrow
In the formula for work, W=F×d, what does d represent?
Depth
Direction
Displacement
Distance
Which of the following statements is true about efficiency?
It can be greater than 100%.
It measures the output force.
It is a ratio comparing input and output energy.
It is measured in joules.
Which of these is an example of work being done?
A person holding a box steady
A car parked on a hill
A book sliding across a table
A tree standing upright
What unit is used to measure power in the International System of Units (SI)?
Joules
Watts
Newtons
Meters
A pulley system is used to lift a heavy box. If 50 J of work is done to lift it, but 10 J of energy is lost to friction, what is the efficiency of the pulley system?
50%
80%
100%
20%
A wedge is a simple machine that converts rotational motion into linear motion.
True
False
Power is defined as the rate at which work is done.
True
False
Using a machine reduces the amount of work required to complete a task.
True
False
A screw is a type of inclined plane wrapped around a cylinder.
True
False
A construction worker uses a lever to lift a heavy rock. If he applies a 200 N force over a 1.5-meter distance and the rock is lifted 0.5 meters with an output force of 600 N, what is the mechanical advantage of the lever?
1
2
3
4
A car engine does 500 J of work in 5 seconds. What is the power output of the engine?
100 W
250 W
500 W
200 W
An engineer designs a pulley system to lift a 205 kg load. The system allows them to lift the load with only 500 N of force. What is the mechanical advantage of this pulley system?
2
4
6
8
