Question

A bullet is fired in a sand filled bucket at a speed of 10m/sec and comes to rest in 5 sec find retarding force​

Answer 1

Correct question :

A bullet of 20 g is fired in a sand filled bucket at a speed of 10m/sec and comes to rest in 5 sec find retarding force.

Given :

• Initial velocity, u = 10 m/s
• Final velocity, v = 0 m/s (as it comes to rest)
• Time taken, t = 5 seconds
• Mass of bullet, m = 20 g

To find :

• Retarding force

According to the question,

➞ v = u + at [First equation of motion]

Where,

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

➞ Substituting the values,

➞ 0 = 10 + a × 5

➞ 0 - 10 = 5a

➞ - 10 = 5a

➞ - 10 ÷ 5 = a

➞ - 2 = a

• So,the retardation is 2 m/s².

Now, we will change the mass in kg,

• Mass, m = 0.02 kg

➞ Force = Mass × Acceleration

Or,

➞ F = ma

➞ F = 0.02 × (- 2)

➞ F = - 0.04

• So, the retarding force is 0.04 Newtons.

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