Question

a body of mass 15kg is moving with the velocity of 18.75 m/s.
find the force required to stop it in 12 seconds?​

Answer 1

Required Answer :

The force required to stop the body in 12 seconds = - 23.4 N

Given :

• Mass of a body = 15 kg
• Initial velocity of the body = 18.75 m/s
• Final velocity of the body = 0 m/s
• Time = 12 seconds

To find :

• Force required to stop the body in 12 seconds

Solution :

To find the force, we need to value of acceleration of the body. So, we will calculate the acceleration of the body by using the first equation of motion.

Calculating the acceleration of the body :-

First equation of motion :-

• v = u + at

where,

• v = Final velocity
• u = Initial velocity
• a = Acceleration
• t = Time

we have,

• v = 0 m/s
• u = 18.75 m/s
• t = 12 s

Substituting the given values :-

⇒ 0 = 18.75 + (a)(12)

⇒ - 18.75 = 12a

⇒ - 18.75 ÷ 12 = a

⇒ - 1.56 = a

Acceleration of the body = - 1.56 m/s²

Now, calculating the force required to stop the body :-

Using formula,

• F = ma

where,

• F = Force
• m = Mass
• a = Acceleration

we have,

• m = 15 kg
• a = - 1.56 m/s²

Substituting the given values :-

⇒ Force = 15 × (-1.56)

⇒ Force = - 23.4

Therefore, the force required to stop the body in 12 seconds = - 23.4 N