Question

Find angle between acceleration and velocity at t = 4 sec

Answer 1

Answer:

π/2+tan`¹/⁴80

Explanation:

acceleration is in vertically downward direction,it affects only vertical volocity

while there is no acceleration in horizontal direction,so horizontal velocity has no change

usin@=100×3/5. ucos@=100×4/5

=60m/s. =80m/s

after 4sec,

in y direction:- in X direction:-

v= u+at. velocity does not changes as

v=60+(-g)t. no acceleration in X direction

v=60-(10)4.

v=20m/s. v=80m/s

tan@ after 4s= v in y direction. 20. 1

-------------------------. = -------. =. ---

v in X direction. 80. 4

@=tan`¹/⁴

hence, acceleration is in vertically downward

and,velocity is in positive x-y plane

then,

angle between acceleration and velocity

=90°+(angle velocity with horizontal)

=π/2+ tan`¹/⁴