Question

A truck weighing 5 * 10^3 kgf and a cart weighting 500 kgf are moving with the same speed compare their kinetic energies?

Answer 1

Answer :-

Given :-

Mass of truck (m₁) = 5 × 10³ kgf

Mass of cart (m₂) = 500 Kg

Since, speeds are same, kinetic energy is directly proportional to the mass.

⟹ K ∝ m

Since :-

⟹ K₁/K₂ = m₁/m₂

⟹ 5 × 10³/500

⟹ 10/1

∴ The ratio of their kinetic energies is 10 : 1.

Learn more :-

Kinetic energy :

• The energy possessed by a body due to its state of motion is called its kinetic energy.

Potential energy :

• The energy possessed by a body at rest due to its position or size and shape is called its potential energy.

Kinetic energy:

⟹ 1/2 × mv²

Where:-

• m = mass
• v = velocity

Potential energy:

⟹ mgh

Where:-

• m = mass
• g = acceleration due to gravity
• h = height

Note:

• Unit of energy is joule, so both K.E and P.E have same units that is joules. (J)

Answer 2

EXPLANATION.

A truck weighing 5 x 10³ kg force.

A cart weighing 500 kg force.

Moving with the same speed complete their kinetic energies.

As we know that,

Formula of :

⇒ Kinetic energy = 1/2 x m x v².

Using this formula in the equation, we get.

⇒ For truck = 1/2 x 5 x 10³ x v². - - - - - (1).

⇒ For cart = 1/2 x 500 x v². - - - - - (2).

Divide equation (1) and (2), we get.

⇒ KE₁/KE₂ = 5 x 10³/5 x 10².

⇒ KE₁/KE₂ = 10/1.

⇒ KE₁/KE₂ = 10 : 1.