Question

calculate the force applied to stop a car of mass 1400 kg in 2 sec if it is moving with a velocity of 10 ms^-1​

Answer 1

Given :

• Mass = 1400 kg
• Time = 2s
• Initial Velocity = 10 m/s
• Final velocity = 0 m/s

Solution :

⇒F = ma

⇒F = m * (v -u)/t

⇒F = 1400 * (0 - 10)/2

⇒F = 1400 * -10/2

⇒F = 1400 * -5

⇒F = -7000 N

Answer 2

SOLUTION :

Mass of the car ( m ) = 1400 kg

time taken to stop the car ( t ) = 2 sec

intial velocity of the car ( u ) = 10 m/s

final velocity of the car ( v ) = 0 m/s

force ( F ) = m × a

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = m \times ( \frac{v - v}{t})$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 1400 \times ( \frac{0 - 10}{2} )$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 1400 \times \frac{( - 10)}{2}$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 700 \times ( - 10)$

= - 7000 N