Explanation:
Let east direction is negative and west direction is positive. The acceleration of an object is given by :
Where
v is the final speed
u is the initial speed
t is the time taken
As the car decelerates, the final speed of the car is less as compared to the initial speed. As a result, its acceleration is negative. It means the car travels eastward and slows down. Hence, this is the required solution.
Answer:
3.467 s
Explanation:
given,
distance , d = 49 mm = 0.049 m
initial speed of the of the rock, v = 17 m/s
time taken by the Heather rock to reach water
using equation of motion
taking downward as negative
4.9 t² + 17 t - 0.049 = 0
now,
t₁ = -3.47 s , 0.0028 s
rejecting negative values
t₁ = 0.0028 s
now, time taken by the ball of Jerry
using equation of motion
taking downward as negative
4.9 t² - 17 t - 0.049 = 0
now,
t₂ = 3.47 s ,-0.0028 s
rejecting negative values
t₂ = 3.47 s
now, time elapsed is = t₂ - t₁ = 3.47 - 0.0028 = 3.467 s