Question

A $6.0N$ horizontal force is applied to a flat rock on a friction less frozen pond, causing it to accelerate at $2.0m/s^2$. What is the mass of the rock?

• A. $12kg$
• B. $0.33kg$
• C. $3.0kg$
• D. $60kg$
• E. $20kg$

Answer 1

The correct option is C $3.0kg$

As the surface of the frozen pond is friction less so there will be no friction force.

By Newton's second law, $F=ma$

So, $m=F/a=6/2=3kg$

Thus, option C will be right.