Question

In an inertial frame of reference, a series of experiments is conducted. In each experiment, two or three forces are applied to an object. The magnitudes of these forces are given. No other forces are acting on the object. In which cases may the object possibly move at a constant velocity of 256m/s

Answer 1

Explanation:

$1.2 \mathrm{N} ; 2 \mathrm{N}$

2.$200 \mathrm{N} ; 200 \mathrm{N}$

4.$2 \mathrm{N} ; 2 \mathrm{N} ; 4 \mathrm{N}$

$5.2 \mathrm{N} ; 2 \mathrm{N} ; 2 \mathrm{N}$

$6.2 \mathrm{N} ; 2 \mathrm{N} ; 3 \mathrm{N}$

$8.200 \mathrm{N} ; 200 \mathrm{N} ; 5 \mathrm{N}$

In only the above cases (i.e 1,2,4,5,6,8 ) the object possibly moves at a constant velocity of $256 \mathrm{m} / \mathrm{s}$

You should have noticed that the sets of forces applied to the object are the same asthe ones in the prevous question. Newton's 1st law (and the 2nd law, too) makes nodistinction between the state of re st and the state of moving at a constant velocity(even a high velocity).

In both cases, the net force applied to the object must equal zero.