Question

A mass of 10 kg is dropped from a height of 50 cm. Find : (a) kinetic energy, and (b) velocity, just as it reaches
the ground. Does the velocity depend on the mass of the particle? Explain.

Answer 1

Mass=10 kg

Height = 50 cm =0.5 m

W= mgh

=10*10*0.5

=50 J

Since kinetic energy=potential energy by law of conservation of energy ..

Answer 2

Given - Mass and height

Find - Given questions

Solution - Correct answers are (a) 50 Joules (b) 3.16 m/s.

When dropped from height, the mass will posses potential energy. On reaching the ground, all the potential energy will be converted to kinetic energy.

So, calculating potential energy first.

Potential energy = mass*g*height.

Taking g as 10 m/s².

Height = 50 centimetres

Height = 0.5 metres

Potential energy = 10*10*0.5

Potential energy = 50 Joules

So, kinetic energy = 50 Joules.

Velocity will be calculated using the formula-

Kinetic energy = 1/2*m*v²

50 = 1/2*10*v²

v² = 10

v = ✓10

v = 3.16 m/s.

Velocity depends on mass of particle. It is related as mass is inversely proportional to square of velocity.

Hence, (a) 50 Joules (b) 3.16 m/s.