Question

A car is moving with a velocity of 60km/hr and possesses energy of 5×105 joules. the mass of the car will be

Answer 1

Answer:

this is totally wrong. how 60 kmph is equal to 1.6 mps

Answer 2

Given :

Velocity (v) = 60 Km/hr

Kinetic Energy (KE) = 5 × 10⁵ J

To Find :

Mass of the car

Solution :

The ability of a body to do work due to its speed alone is called kinetic energy.

   Kinetic Energy (KE) = $\frac{1}{2} mv^2$                 (m = mass; v = velocity)

⇒    5 × 10⁵                    = $\frac{1}{2}$ × m × (60×$\frac{5}{18}$)²

⇒    5 × 10⁵                    = $\frac{1}{2}$ × m × 277.78

⇒     m                           = $\frac{10^6}{277.78}$

∴      m                           =  3.6 × 10³ kg = 3600 Kg

Hence, the mass of the car is 3600 Kg