Question

an object is moving along a circular path with a speed of 20 m/s . points a and b are diametrically opposite. find the difference in velocities of the object between points a and b.​

Answer 1

Answer:

40m/s

Explanation:

since they are diametrically opposite, their velocities are pointing in opposite directions.

v at a=20m/s

v at b=-20m/s

va-vb=20-(-20)=20+20=40m/s

Answer 2

Given:

An object is moving along a circular path with a speed of 20 m/s. Points 'a' and 'b' are diametrically opposite.

To find:

Difference in velocity between the two points ?

Calculation:

• Please see the vector diagram. We can say :

At point 'a' :

$v_{a} = 20 \hat{j}$

At point 'b' :

$v_{b} = 20( - \hat{j})$

$\implies \: v_{b} = - 20 \hat{j}$

Now, difference between velocities :

$v_{a} - v_{b} = 20 \hat{j} - ( - 20 \hat{j})$

$\implies \: v_{a} - v_{b} = (20 + 20) \hat{j}$

$\implies \: v_{a} - v_{b} = 40\hat{j}$

$\implies \: v_{a} - v_{b} = 40 \: m {s}^{ - 1} \: \hat{j}$

So, magnitude of difference is 40 m/s.