Answer:

Explanation:
given,
weight of swimmer = 510 N
length of ledge, L = 1.75 m
vertical height of the cliff, h = 9 m
speed of the swimmer = ?
horizontal velocity of the swimmer should be that much it can cross the wedge.
distance = speed x time
d = v_x × t
1.75 = v_x × t ........(1)
now,time taken by the swimmer to cover 9 m
initial vertical velocity of the swimmer is zero.
using equation of motion for time calculation


t² = 1.938
t = 1.39 s
same time will be taken to cover horizontal distance.
now, from equation 1
1.75 = v_x × 1.39

horizontal speed of the swimmer is equal to 1.26 m/s
In order to answer this, we will set up a simple ratio as such:
1 calorie = 4.184 joules
1 kilocalorie = 1000 calories
1 kilocalorie = 4,184 joules
250 kilocalories = x joules
Cross multiplying the second and third equations, we get:
x joules = 4,184 * 250
250 kilocalories are equivalent to 1,046 kJ
Answer:
Part 1) Time of travel equals 61 seconds
Part 2) Maximum speed equals 39.66 m/s.
Explanation:
The final speed of the train when it completes half of it's journey is given by third equation of kinematics as

where
'v' is the final speed
'u' is initial speed
'a' is acceleration of the body
's' is the distance covered
Applying the given values we get

Now the time taken to attain the above velocity can be calculated by the first equation of kinematics as

Since the deceleration is same as acceleration hence the time to stop in the same distance shall be equal to the time taken to accelerate the first half of distance
Thus total time of journey equals
Part b)
the maximum speed is reached at the point when the train ends it's acceleration thus the maximum speed reached by the train equals 
Answer:
Yes, but only if it's sunny.
Explanation:
As you know, solar panels generate energy through the sun's rays of light (better known as sunlight). Therefore, as long as the sun is shining high in the sky, the car will generate electricity and be able to function. If this vehicle was only powered by solar panels, it would not function during the night, in cloudy areas, and/or in dark places (such as parking garages or home garages).
Hope this helps!