Answer:
<em>a. The rock takes 2.02 seconds to hit the ground</em>
<em>b. The rock lands at 20,2 m from the base of the cliff</em>
Explanation:
Horizontal motion occurs when an object is thrown horizontally with an initial speed v from a height h above the ground. When it happens, the object moves through a curved path determined by gravity until it hits the ground.
The time taken by the object to hit the ground is calculated by:

The range is defined as the maximum horizontal distance traveled by the object and it can be calculated as follows:

The man is standing on the edge of the h=20 m cliff and throws a rock with a horizontal speed of v=10 m/s.
a,
The time taken by the rock to reach the ground is:


t = 2.02 s
The rock takes 2.02 seconds to hit the ground
b.
The range is calculated now:

d = 20.2 m
The rock lands at 20,2 m from the base of the cliff
Mass = 0.201kg
Energy = 15J
temperature change = 10C
Energy(E) = mass(m) × specific heat capacity(c) × temperature change(θ)
we can rearrange this to make specific heat capacity the subject
c =

c =

c =7.46268657
The complete sentence is:
A calorimeter directly measures changes in temperature in order to calculate specific heat.
In fact, the amount of energy acquired/released by a substance is directly proportional to its change in temperature due to the equation

where Q is the amount of energy, m is the mass of the substance, Cs is the specific heat of the substance and
is the change in temperature. Therefore, by knowing Q, m and by measuring the change in temperature, it is possible to calculate Cs, the specific heat capacity of the substance.
We are given with the x and y components of Vector A and B. In this case, we compute the resultant of both components of each vector. The vector is equal to the square root of the sum of the squares of the components. A is equal to 2.60 cm. B is equal to 5.56 cm. B is found in quadrant Iv and has an angle of 42.447 degrees as a terminal angle. A has an angle of 59.98 degrees.
a. 5.6082 < -15.53 degreesc. 6.63 <-64.98 degreesb. x = 6.63 cos -64.98 degrees = 2.80 y = 6.63 sin -64.98 degrees = -6.00