Question

What is the force acting on an object of mass 5 kg if it increases its velocity from 3m/s to 7 m/s in 2 seconds? *

Answer 1

Given :

• Initial velocity, u = 3 m/s

• Final velocity, v = 7 m/s

• Time, t = 2 seconds

• Mass of an object, m = 5 kg

To find :

• Acceleration, a

• Force, F

According to the question,

By using Newtons first equation of motion we will find acceleration then by using F = ma we will find force.

➞ v = u + at

Where,

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

➞ Substituting the values,

➞ 7 = 3 + a × 2

➞ 7 - 3 = 2a

➞ 4 = 2a

➞ 4 ÷ 2 = a

➞ 2 = a

So,the acceleration is 2 m/s².

Now,

➞ Force = Mass × Acceleration

Or,

➞ F = ma

➞ Substituting the values,

➞ F = 5 × 2

➞ F = 10 N

So,the force acting on an object is 10 Newton.