Erosion - The process in which water, ice, wind, or gravity moves pieces of rock or soil
When a spoon is in a cup of water, is called refraction.
Answer:
(a) vo = 24.98m/s
(b) t = 5.09 s
Explanation:
(a) In order to calculate the the initial speed of the ball, you use the following formula:
(1)
y: vertical position of the ball = 2.44m
yo: initial vertical position = 0m
vo: initial speed of the ball = ?
g: gravitational acceleration = 9.8m/s²
t: time on which the ball is at 2.44m above the ground = 5.00s
You solve the equation (1) for vo and replace the values of the other parameters:

The initial speed of the ball is 24.98m/s
(b) To find the time the ball takes to arrive to the ground you use the equation (1) for y = 0m (ground) and solve for t:

The time that the ball takes to arrive to the ground is 5.09s
The amount of energy needed to increase the temperature of a substance by

is given by

where
m is the mass of the substance

is its specific heat capacity

is the increase in temperature
The water volume is

, since its density is

, the mass of this sample of water is

The water specific heat capacity is

and the increase in temperature is

Therefore, the amount of energy needed is