Question

If a ball of 20 gm was brought to rest after covering a distance of 10 m moving at a speed of 50m/s, what was the magnitude of this applied force:
Please help me actually it's a question of my question paper of physics and i can't solve it ​

Answer 1

QUESTION-:

If a ball of 20 gm was brought to rest after covering a distance of 10 m moving at a speed of 50m/s, what was the magnitude of this applied force ?

EXPLANATION-:

We know that-:

$\rightarrow \underline{\boxed{\bf\; F=ma }}$

Where-:

• F= Force applies
• m= Mass of body
• a= Acceleration of the body

So let's first calculate the acceleration-:

We know that-:

$\rightarrow \boxed{\bf\; v^2=u^2+2as }$

Putting values -:

$\rightarrow \bf\; 0=2500+2 \times a \times 10\\\\\rightarrow \bf\; a=\frac{2500}{-20} \\\\\rightarrow \boxed{\tt a=125\;m/s^2 }$

Now let's find the force-:

$\rightarrow \bf\; F=\frac{1}{50}\times 125 \qquad \qquad \{20\;gm=\frac{1}{50}\;kg\}\\\\\rightarrow \boxed{\bf\; F=-2.4\;N}$

So the force applies is 2.4 N and the magnitude is 2.4 N .