The energy of 9800J was used to lift the 70kg weight at which height the weight was lifted?

To find the height, we use the formula for gravitational potential energy:

Potential Energy (PE) = m × g × h

Where:

PE = 9800 J (Energy used)

m = 70 kg (Mass of the object)

g = 10 m/s² (Acceleration due to gravity, commonly used in numerical problems)

h = ? (Height)

Substituting the given values:

9800 = 70 × 10 × h

9800 = 700h

h = 9800 ÷ 700 = 14 m

Therefore, the 70 kg object was lifted to a height of 14 metres.

Note: Options with negative height are incorrect because the object is being lifted upward, so the height must be positive.