Question

7. Alice holds a black belt in Taekwondo and her fist has a mass of 0.5 kg. Her fist obtains a velocity of 5 m/s in 0.1 seconds from rest. Evaluate the average net force applied to the fist.

Answer 1

Answer:

25N

Explanation:

Find acceleration first

A=v-u/t

acceleration = 5/0.1s =50m/s^2

then find net force using f=mass x acceleration, which iin this case is 25N

Answer 2

Answer: 25 N

Explanation:

the fist hit by the black belt Alice in the Taekwondo has been given to have a mass of 0.5 kg which acquires a velocity of 5 m/s in a time of 0.1 sec, therefore, the average net force which is being applied to the fist can be calculated by the following method,

Given,   mass m=0.5 kg, velocity v=5 m/s, time t=0.1 sec

As we know that, acceleration

$a=\frac{v-u}{t}=\frac{5-0}{0.1}=50 \mathrm{m} / \mathrm{s}^{2}$

Thereby,

$\text { Force }=\text { mass } \times \text { acceleration }=0.5 \times 50=25 N$