Answer:
Your average speed is 60 kilometers per hour
Explanation:
240 divided by 4 is 60
240/4=60
Answer:
* roller skates and ice skates.
* roller coaster
Explanation:
One of the best examples for this situation is when we are skating, in the initial part we must create work with a force, it compensates to move, after this the external force stops working and we continue movements with kinetic energy, if there are some ramps, we can going up, where the kinetic energy is transformed into potential energy and when going down again it is transformed into kinetic energy. This is true for both roller skates and ice skates.
Another example is the roller coaster, in this case the motor creates work to increase the energy of the car by raising it, when it reaches the top the motor is disconnected, and all the movement is carried out with changes in kinetic and potential energy. In the upper part the energy is almost all potential, it only has the kinetic energy necessary to continue the movement and in the lower part it is all kinetic; At the end of the tour, the brakes are applied that bring about the non-conservative forces that decrease the mechanical energy, transforming it into heat.
In order for the object not to slip, the component of the weight parallel to the surface must be equal to the frictional force (which acts in the opposite direction):

The parallel component of the weight is:

where m is the object mass and

is the angle of the inclined plane.
The frictional force is

where

is the coefficient of static friction.
Equalizing the two forces, we have

from which we find

and so, in our problem the coefficient of static friction must be
Answer:
21.9 seconds
Explanation:
lets say the speed of sound at room temp 343m/s and one kilometer is 1000 meters. so 7.5 kilometers is equal to 7500 meters and we divide this number by 343 and we get 21.8 seconds
The difference between the distance and the displacement is the speed is a scalar while displacement is a vector.
<h3>What is the distance an the displacement?</h3>
The distance is the difference between two points while the displacement is the difference between two points in a specified direction. Given that speed is a scalar and the displacement is a vector. It follows that we must take the displacement when obtaining the displacement.
Thus, the distance that is covered after one lap is the circumference of the circle = 2πr = 2 * 3.142 * 25 = 31 m Then for 2 laps = 62 m
The displacement is obtained when we take the direction into consideration. Owing to the fact that the runner returns to the starting point each time, the displacement is zero.
Learn more about displacement:brainly.com/question/11934397
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