Answer:
-36.4 m/s
Explanation:
final velocity= initial velocity + acceleration x time
7 + (-9.8)(3)= -36.4 m/s
Kepler's first law - sometimes referred to as the law of ellipses - explains that planets are orbiting the sun in a path described as an ellipse. An ellipse can easily be constructed using a pencil, two tacks, a string, a sheet of paper and a piece of cardboard. Tack the sheet of paper to the cardboard using the two tacks. Then tie the string into a loop and wrap the loop around the two tacks. Take your pencil and pull the string until the pencil and two tacks make a triangle (see diagram at the right). Then begin to trace out a path with the pencil, keeping the string wrapped tightly around the tacks. The resulting shape will be an ellipse. An ellipse is a special curve in which the sum of the distances from every point on the curve to two other points is a constant. The two other points (represented here by the tack locations) are known as the foci of the ellipse. The closer together that these points are, the more closely that the ellipse resembles the shape of a circle. In fact, a circle is the special case of an ellipse in which the two foci are at the same location. Kepler's first law is rather simple - all planets orbit the sun in a path that resembles an ellipse, with the sun being located at one of the foci of that ellipse.
As we know that as per Newton's II law we have

here we will have
= change in momentum
= time interval in which momentum is changed
now in order to have least injury during jumping we need to have least force on the jumper
so in order to have least force we can say that the momentum must have to change in maximum time so that amount of force must be least
So we need to increase the time in which momentum of the system is changed
Materials required for the experiment of limiting force borne by string:-
- String balance
- weights
- light strings
- weight hanger
- pan for spring balance
- Sand
Steps of procedure for for the experiment of limiting force borne by string:-
- First we have to tie a light string to the fixed support and then tie the other end with the weight hanger consists of weight.
- Add additional weight to the hanger again and again. And continue the same until the string is broken.
- Note down the weight (x) where the string is broken.
- Suspend spring balance to a support.
- Tie the light string at the end of the balance and at the other end suspend the pan for spring balance.
- Now place the weights (x-100 grams) in pan.
- Observe the reading in the spring balance.
- Add a small amount of sand in the pan by observing the readings.
- same is to be done till the string is broken.
Learn more about limiting force here:- brainly.com/question/11371672
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