A plane is revolving around the earth with a speed 100 km/hr at a constant height from the surface of earth. The change in the velocity as it travels half circle is
Answer is 200km/hr
First things I noticed : There is no acceleration of the plane given.There is no constant force as well given.Then why is change in velocity simply not 0.
2 Drew a vector 100 j upwards and 100(-j) downwards. When two vectors are opposite they cut each other.Why don’t they do it here ? =0
Please help in this
We want the difference in the two vectors, $v_0 = 100\hat{j}$ and $v_1 = -100\hat{j}$ so $$v_0 + v_1 = 0$$ but the magnitude of the change in velocity is $$|v_0 - v_1| = |200 \hat{j}| = 200(km/hr)$$An massive object which moves in a circle must be accelerating, in fact the magnitude of it's acceleration must be $a = \frac{v^2}{r}$ where $v$ is the linear velocity and $r$ is the distance from the center of the circle.