Is this a question or a statement. This statement would be incorrect. <span />
A) Calling F the intensity of the horizontal force and d the displacement of the block across the floor, the work done by the horizontal force is equal to

b) The work done by the frictional force against the motion of the block is equal to:


Part of these 105.1 Joules of work becomes increase of thermal energy of the block (

), and part of it becomes increase of thermal energy of the floor (

). We already know the increase in thermal energy of the block (38.2 J), so we can find the increase in thermal energy of the floor:

c) The net work done on the block is the work done by the horizontal force F minus the work done by the frictional force (the frictional force acts against the motion, so we must take it with a negative sign):

For the work-energy theorem, the work done on the block is equal to its increase of kinetic energy:

So, we have
Explanation:
The given statement is absolutely true. this is because magnitude of a vector is always non negative, it can not be zero unless its a zero vector. So, in the given question, final position vector of a moving object has a smaller magnitude than the initial position vector, so, magnitude is neither zero nor negative. Hence, it has a positive magnitude.
Answer: Option (A) is the correct answer.
Explanation:
Relation between kinetic energy and temperature is as follows.
As, kinetic energy is directly proportional to temperature. So, when there will be increase in temperature then there will also occur increase in kinetic energy of the particles of a substance.
And, when gas particles move slowly then it means kinetic energy of gas particles is very low. It also implies that temperature is low.
Thus, we can conclude that temperature will increase best describes the outcome of increasing the kinetic energy of the molecules in the above picture.
The pressure inside the container will be <u>9.39×10⁴Pa</u>
At constant volume, the pressure in a container is directly proportional to its absolute temperature.
If air in a container is sealed at 20⁰C at a pressure equal to the atmospheric pressure and cooled to 2.00⁰C, the pressure inside the container falls.
Convert the temperature in Celsius to Kelvin.

Use the expression for the pressure law.

Substitute 100,000 Pa for P₁, 293.16 K for T₁ and 275.15K for T₂.

The pressure in the container (correct to 2 sf) is <u>9.39×10⁴Pa</u>