Answer:
a) 17.49 seconds
b) 13.12 seconds
c) 2.99 m/s²
Explanation:
a) Acceleration = a = 1.35 m/s²
Final velocity = v = 85 km/h = 
Initial velocity = u = 0
Equation of motion

Time taken to accelerate to top speed is 17.49 seconds.
b) Acceleration = a = -1.8 m/s²
Initial velocity = u = 23.61\ m/s
Final velocity = v = 0

Time taken to stop the train from top speed is 13.12 seconds
c) Initial velocity = u = 23.61 m/s
Time taken = t = 7.9 s
Final velocity = v = 0

Emergency acceleration is 2.99 m/s² (magnitude)
Answer:
it b
Explanation:
bc A water droplet falling in the atmosphere is spherical
Velocity is the speed and direction combined.
So, the two jets both are going at the same speed.
But they are going in different directions, so their velocities are different.

The most effective forces on the object are the backward force of air resistance relatively very small in magnitude, and the force of gravity. Because the spiral path of the satellite is not perpendicular to the gravitational force, one element of the gravitational force pulls forward. at the satellite to do fantastic work & make its speed increase.
<h3>What is called gravitational force?</h3>
Gravity, additionally referred to as gravitation, is a force that exists amongst all material gadgets withinside the universe. For any objects or particles having nonzero mass, the force of gravity tends to draw them in the direction of each other. Gravity operates on objects of all sizes, from subatomic particles to clusters of galaxies.
To learn more about gravitational force, visit;
brainly.com/question/9266911
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