7.2 Measurement of force

Measuring force

• The SI unit for measuring force is NEWTON (N).
• A force can be measured using Spring balance or Newton balance.
• The reading of the spring balance is the measurement of the magnitude of the force exerted.
• The spring balance works on the principle that the extension of the spring is directly proportional to the force acting on it.
• The greater the force acting on the spring, the larger the extension of the spring.
• Extension of the spring depends on the force of gravity acting on it.

Diagram 1 : Spring balance

Weight VS Gravity

• The weight of an object depends on pull of gravity.
• The force of gravity on the moon is only one-six of the force of gravity on earth.
• Thus, different object will have different weight on the earth and the moon.

Diagram 2 : Different size of earth and moon

Calculation 

 

Note : 1 kilogram (kg) = 10 newton

Diagram 3 : Weight and Mass

The answer depends on question. If the question wants you to give the answer in g, so, 

convert kg to g. So, after converting, 0.5 kg = 500 g.