Answer:
The average speed for the entire run is 12 km/h.
Explanation:
The average speed is given by the following equation:
Where:
: is the total distance
: is the total time
If during the first hour, they ran a total of 13 kilometers and then, they ran 5.0 kilometers during the next half an hour we have:
Hence, the average speed is:
Therefore, the average speed for the entire run is 12 km/h.
I hope it helps you!
Rotation. The Earth rotates around the sun on it’s axis. Depending how far north or south you live, and the angle of the sun at different times of year gives you the amount of daylight or darkness you will receive. So the length of day or night depends on how much the sun is able to reach the spot on a round object such as the planet Earth.
Answer:
The given figure shows two men M and N facing two flat and hard walls, wall 1 and wall 2. Man N fires a gun. Man M hears two echoes, one from wall 1 and second from wall 2. The speed of sound in
air is given to be 325 m/s. After the firing of the gun by the man N, the man M will hear the first echo in how many seconds?
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A positive way that Friction helps in your every day life would be when you drive to work or school. There is friction acting upon your tires, without it you would continue to constantly move forwards until you have struck something, bringing you to a halt. Therefore friction is a positive in this case, however friction can also be a negative in your everyday life. This is possible because friction can be used against you, say you were dragging a box from point A to point B up a hill. You must use mechanical energy however going uphill already presents a problem, now if the wind were to blow you would be moving against friction, this is a negative.
