Answer:
An <u>applied force</u> is a force that is applied to an object by a person or another object. If a person is pushing a desk across the room, then there is an applied force acting upon the object. The applied force is the force exerted on the desk by the person.
A <u>friction force</u> is the force exerted by a surface as an object moves across it or makes an effort to move across it. There are at least two types of friction force - sliding and static friction. Though it is not always the case, the friction force often opposes the motion of an object. For example, if a book slides across the surface of a desk, then the desk exerts a friction force in the opposite direction of its motion. Friction results from the two surfaces being pressed together closely, causing intermolecular attractive forces between molecules of different surfaces. As such, friction depends upon the nature of the two surfaces and upon the degree to which they are pressed together. The maximum amount of friction force that a surface can exert upon an object can be calculated using the formula below:
= µ • 
Answer: 1479watts
Explanation:
Power is defined as the energy expended or work done in a specific time.
Mathematically,
Power = Workdone/time taken
Since work done is force × distance
Power = force × distance/time
Force = Mary's weight = 87N
Distance = height of the flight = 102meters
Time = 6.0seconds
Substituting in the formula we have;
Power = 87 × 102/6
Power = 1,479watts
Note that the time must be in seconds before usage. If its given in minutes, you will have to convert to seconds
The physical model of the sun's interior has been confirmed by observations of neutrino and seismic vibrations.
<u>Explanation:</u>
Sun's interior is composed of very high temperature and solar flares. So it is very difficult to understand the interior of the sun. But by using the vibrations of neutrino and seismic waves emitted by the solar waves, the physical model can be assumed.
As the interior of the sun performs continuous chain of hydrogen cycle. So the continuous emission of energy from the chain reaction releases neutrino. So these vibrations in neutrino and seismic vibrations, the physical model can be assumed easily.
The average acceleration can be found by dividing the final speed by the time taken to reach said point so in this case you divide 60 by 8 resulting in 7.5 which will be your answer
A - the amount of time needed to travel the distance
The formula for speed is distance/time and the unit is m/s. Therefore you divide the distance travelled by the time it took to travel it.
