Answer:
Burning Paper
Explanation:
This is a chemical reaction, because new substances are formed
To solve the exercise it is necessary to apply the concepts related to Newton's Second Law, as well as the definition of Weight and Friction Force.
According to the problem there is a movement in the body and it is necessary to make a sum of forces on it, so that

There are two forces acting on the body, the Force that is pushing and the opposing force that is that of friction, that is

To find the required force then,

By definition we know that the friction force is equal to the multiplication between the friction coefficient and the weight, that is to say





Therefore the horizontal force applied on the block is B) 230N
Answer: 9.0 atm
Explanation:
To calculate the new pressure, we use the equation given by Boyle's law. This law states that pressure is directly proportional to the volume of the gas at constant temperature.
The equation given by this law is:

where,
are initial pressure and volume.
are final pressure and volume.
We are given:

Putting values in above equation, we get:

Thus new pressure of 150 ml of a gas that is compressed to 50 ml is 9.0 atm
Answer:
25 min, 48 sec
Explanation:
Alan:
t = d/v
= 400 mi / 46 mph = 8.70 hr
So it took Alan 8.70 hrs; from 8 am, that's 4:42 pm that he arrives.
t = d/v
= 400 mi / 55 mph = 7.27 hr
So it took Beth 7.27 hrs; from 9 am, that's 4:16:12 that she arrives.
4:42 - 4:16:12 = 25.8 minutes = 25 minutes, 48 sec
Answer:

the mass of body B must be greater than the mass of body A
Explanation:
Newton's second law establishes a linear relationship between the force, the mass of the body and its acceleration
F = m a
a = F / m
Let's analyze this expression tells us that the force is of equal magnitude for the two bodies, but body A goes faster than body B, this implies that it has more relationships
a_A > a_B
Therefore, for this to happen, the mass of body B must be greater than the mass of body A