Answer:
1.4 m/s
Explanation:
The final velocity of the ball can be found by using the following SUVAT equation:
where
v is the final velocity
u is the initial velocity
a is the acceleration
d is the distance travelled
In this problem,
u = 4.0 m/s
d = 14 m
a = -0.50 m/s^2
Solving the equation for v,
(a) 8927 mi/h
In order to calculate the average speed, we need to convert the time (t=5.0 y) into hours first. In 1 year, we have 365 days, each day consisting of 24 hours, so the time taken is:
The distance covered by the spacecraft is
Therefore, the average speed is just the ratio between the distance covered and the time taken:
(b) 35 minutes (2097 seconds)
The transmitted signals (which is a radio wave, which is an electromagnetic wave) travels back to the Earth at the speed of light:
Since 1 miles = 1609 metres, the distance covered by the signal is
So, the time taken by the signal will be
And since 1 minute = 60 sec, the time taken is