Answer:
B. 
Explanation:
Assuming we are dealing with a perfect gas, we should use the perfect gas equation:
With T the temperature, V the volume, P the pressure, R the perfect gas constant and n the number of mol, we are going to use the subscripts i for the initial state when the gas has 20 cubic inches of volume and absolute pressure of 5 psi, and final state when the gas reaches 10 psi, so we have two equations:
(1)
(2)
Assuming the temperature and the number of moles remain constant (number of moles remain constant if we don't have a leak of gas) we should equate equations (1) and (2) because 
, 
and R is an universal constant:
, solving for 
A single fixed pulley can be used to raise or lower lightweight objects.
Option b
<u>Explanation:</u>
A pulley is a simple machine tool which is used to make lifting or lowering tasks easy. A single fixed pulley is a system involving only one pulley fixed on a constant rigid support with a rope wrapped around the wheel. Such a system can be used only to change the direction of applied force in raising or lowering small, lightweight objects which need minimal work force.
A single fixed pulley system helps only in redirecting the applied force direction by using a rope and wheel assembly. The work done in such a case remains the same and hence it is not preferred to use it in lifting heavy objects. Neither is the required force reduced in case of a single fixed pulley system. A movable pulley helps in achieving (A) and (C).
Answer:
Explanation:
The force of kinetic friction on the block is defined as:
Where 
is the coefficient of kinetic friction between the block and the surface and N is the normal force, which is always perpendicular to the surface that the object contacts. So, according to the free body diagram of the block, we have:
Replacing this in the first equation and solving for :
Answer:
C
Explanation:
Because *censored*. Then the element *censored* your answer
Answer:
Momentum of system = 37.2 Kgm/s.
Explanation:
<u>Given the following data;</u>
- Mass A = 5 kg
- Velocity A = 6 m/s
- Mass B = 12 kg
- Velocity B = 0.6 m/s
To find the momentum of the system;
Momentum can be defined as the multiplication (product) of the mass possessed by an object and its velocity. Momentum is considered to be a vector quantity because it has both magnitude and direction.
Mathematically, momentum is given by the formula;
Momentum = mass * velocity
<u>For object A;</u>
Momentum A = 5 * 6
Momentum A = 30 Kgm/s
<u>For object B;</u>
Momentum B = 12 * 0.6
Momentum B = 7.2 Kgm/s
Next, we would determine the momentum of this system using the formula;
Momentum of system = Momentum A + Momentum B
Substituting the values into the formula, we have;
Momentum of system = 30 + 7.2
<em>Momentum of system = 37.2 Kgm/s.</em>
