Answer:
b)
Explanation:
Normal force, is always directed upward the surface over which is placed the object, and can adopt any value, as required to meet Newton's 2nd Law.
In this case, as the external force on the suitcase pulls upward, in order to counteract the influence of gravity, normal force is less than the weight of the suitcase, as follows:
F + Fn = m*g
⇒ Fn = m*g - F
So, the normal force is equal to the magnitude of the weight of the suitcase (m*g) minus the magnitude of the force of the pull (F) which is the same expressed by the statement b.
The third law of thermodynamics,the principle of temperature.
This law states that the entropy at 0 is always equel to 0.
This means that it is impossible to cool down a perfect 0 or absolute 0(-273.15 C)
Answer:

Explanation:
From the question we are told that
Radius of vertical r= 8m
Force exerted by passengers is 1/4 of weight
Generally the net force acting on top of the roller coaster is give to be

where


Generally the net force is given to be 




Mathematical we can now derive V




Therefore the speed of the roller coaster is given ton be 
It would be best to cover the cardiac, smooth, and skeletal muscles! =)
Answer:
Explanation:
Let the forward displacement is taken is positive, and the backward displacement is taken is negative.
first displacement = + 18 cm
second displacement = - 6 cm
third displacement = - 12 cm
net displacement = 18 - 12 - 6 = 0 cm