Answer:
m = 4
Explanation:
We have,
You apply a force of 600 N to the branch which acts as a lever. It means it is input force, IF = 600 N
The rear of the truck weighs 2,400 N. It means it is output force, OF = 2400 N
The ratio of output force to the input force is equal to the mechanical advantage of the lever arm. It is given by :

So, the mechanical gain of the lever arm is 4.
Answer:
The air is contained at a high pressure in the tube. When it escapes from a small orifice, it suddenly expands. A large amount of its heat is absorbed in the process of expansion resulting in considerable fall in its temperature. This is why the escaping air feels cold.
Answer:
(d) a net external force must be acting on the system
Explanation:
Momentum is given as the product of mass and velocity.
P = MV
According to Newton's second law of motion, " Force applied to a body (system) is directly proportional to the rate of change of momentum of the body (system) which takes place in the direction of the applied force (external force).
F ∝ΔMV
Therefore, If the total momentum of a system is changing, a net external force must be acting on the system.
(d) a net external force must be acting on the system
<span>First, she should put the sample in a test tube and place it in a centrifuge. This would cause the red blood cells to move to the bottom because of their higher density. Next, she would be able to decant the plasma and analyze it separately from the red blood cells.</span>