Question

A constant force act on an object of mass 10 kg for duration of 4seconds its increases the object velocity from 8ms to 20ms find the magnitude of the applied force

Answer 1

Given :

• Initial velocity, u = 8 m/s
• Final velocity, v = 20 m/s
• Time, t = 8 seconds
• Mass, m = 10 kg

To find :

• Force applied

According to the question,

➞ v = u + at

Where,

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

➞ 20 = 8 + a × 4

➞ 20 - 8 = 4a

➞ 12 = 4a

➞ 12 ÷ 4 = a

➞ 3 = a

So,the acceleration is 3 m/s².

Now,

➞ Force = Mass × Acceleration

Or,

➞ F = ma

➞ F = 10 × 3

➞ F = 30

So,the force applied is 30 Newtons.

Answer 2

Given:-

• Mass, m = 10 kg

• Time taken ,t = 4 s

• Initial velocity ,u = 8 m/s

• Final velocity ,v = 20 m/s

To Find:-

• Magnitude of Force ,F

Solution:-

Firstly we calculate the acceleration of the object.

Acceleration is defined as the rate of change of velocity at per unit time.

• a = v-u/t

where,

v is the final velocity

a is the acceleration

u is the initial velocity

t is the time taken

Substitute the value we get

→ a = 20-8/4

→ a = 12/4

→ a = 3m/s²

Acceleration of object is 3m/s²

Now, Calculating the Magnitude of Force

As we know that Force is defined as the product of mass and acceleration.

• F = ma

where,

F is the force

m is the mass

a is the acceleration

Substitute the value we get

→ F = 10×3

→ F = 30 N

Therefore,the magnitude of force is 30 Newton.