Answer:
, where the minus indicates the direction is opposite to that of the throw.
Explanation:
a)
Since MKS stands for meter-kilogram-second and we know that:



We can write that:



These are conversion factors, equal to 1, so multiplying our results by them won't change their value, only their units.
So we have that:



b)
Newton's 2nd Law tells us that F=ma, and the definition of acceleration is
, so we have:

Taking the throw direction as the positive one, for our values we have:

Kinetic energy increases, potencial energy decreases,
kinetic energy + potential energy = energy, energy can not be destroyed, just transformed
Answer:
The average speed of the earth in its orbit is 
Explanation:
The average distance between the Earth and the Sun is
.
The average speed of the earth in its orbit can be found by the next equation :
(1)
Where r is the radius and T is the period.
In this case, the orbit of the Earth can be considered as a circle
(
) instead of an ellipse.
It takes 1 year to the Earth to make one revolution around the Sun. Therefore, its period will be 365.25 days.
Notice that to express the period in terms of seconds, the following is needed:
⇒ 
Then, equation 1 can be used:


<h2>
Time taken by dryer to come up to speed is 1.625 seconds.</h2>
Explanation:
We have equation of motion v = u + at
Initial velocity, u = 0 rad/s
Final velocity, v = 5.2 rad/s
Time, t = ?
Acceleration, a = 3.2 rad/s²
Substituting
v = u + at
5.2 = 0 + 3.2 x t
t = 1.625 s
Time taken by dryer to come up to speed is 1.625 seconds.