Question

4. A car moving at 180 km/hr domes to stop in 25 sec. what was its acceleration. a) 2m/s2 b)-2 m/s2 CX 7.5 m/s2 d) -7.5 m/s? 5. The position of a particle is given byx = 8.0tî – 6.0j + 3.0t?k. Find the velocity and acceleration of the particles. a) 8.01 + 6.0tk, 6.0k b) 8.0 – 6.0ị, - 6.09 c) 8.04 – 6.0tk, – 6.0j d) -6.09 + 6.0tk. – 6.0j 6. A body is throw with velocity 50 m/s at 580 to the Horizontal. Find the height where velocity is zero. a) 1 m b) 22 m c)15m d)none​

Answer 1

Explanation:

Correct option is

B

10 ms−1

Velocity is vector quantity so direction matters.

vi=25m/s,vf=−25m/s.

Δv=(−25)−25=−50m/s

Average acceleration =ΔtΔv=550=10ms−2.