Principles of Science Mock Paper 2

From a 50 metre cable drum, you have installed 13.6 metres of cable.                   
What percentage of cable has been used? 

• 3.8%

• 72.8%

• 27.2%

• 65%

An insulation resistance tester is used to record the following values:                             
55MΩ, 72MΩ, 55MΩ, 18.5Ω, 10 MΩ and 89MΩ. What is the mean of
these values?

• 49.9MΩ

• 89MΩ

• 55MΩ

• 18.5MΩ

The SI unit for resistivity is?

• a)    Ohm

• M

• R

• Ωm

Potential Difference is measured in?

• Amps

• Volts

• Joules

• Newton's

In the SI system, time is measured in?

(a)  

1)    Lifting a load an electric motor uses 180,000 Joules of energy in 1 ½ minutes.

What is the power rating of the motor?

Answer in Watts amount.

Mathematical Equivalence

ON

Crowbars are an example of what type of lever?

• Class 1

• Class 2

• Class 3

• Class 4

Force on a load is considered to be a combination of:

• energy and work done

• weight and energy

• time and acceleration

• Mass and Gravity

1)    An electric motor has a 1.8 kW input and an efficiency of 88%.
What is the motor’s output?

Answer is required to be in Kw

Mathematical Equivalence

ON

A four pulley system is required to lift a load force of 20000 Newton’s.

What is the effort force required to lift this load?                         

a

• 5000N

• 800000N

• 5000 Kg

• 10000 N