Question

A hammer of 1 kg strikes with the wall with 6 m/s and

rests in 0.1 sec. So the impulse is ……

(A) -6 Ns (B) -5 Ns

(C) -3 Ns (D) -9 Ns​

Answer 1

Impulse is - 6 Ns

Option A

Given

A hammer of 1 kg strikes with the wall with 6 m/s and  rests in 0.1 sec

To Find

Impulse

Knowledge Required

Impulse is defined as product of force and time

$\to \rm J=Ft\\\\\to \rm J=(ma)t\\\\\to \rm J=m\left( \dfrac{v-u}{t}\right)t\\\\\to \bf \pink {J=m(v-u)}$

where ,

• J denotes impulse
• m denotes mass
• v denotes final velocity
• u denotes initial velocity

Solution

• m = 1 kg
• u = 6 m/s
• v = 0 m/s

Apply formula ,

$\to \rm J=1(0-6)\\\\\bf \to \green{J=-6\ Ns\ \; \bigstar}$

So , Impulse is - 6 Ns