91影视

It is friction that prevents the slide of two or more objects that have different coefficients of friction. Friction may come in several forms: When two solid surfaces come into contact, dry friction acts as a counterforce to the movement of the two surfaces relative to each other.

The slope of momentum-time graph will give acceleration.

In first experiment, the cart is originally at rest, a push is given to the cart, the cart moves in positive x direction and slowly it comes to rest, in this case the fan on cart is off. The second graph satisfies the condition here the graph starts with rest accelerates to a positive direction, reaches its maximum acceleration and after this point its acceleration starts to decrease slowly at slow rate and at last the cart stops.

In the second experiment, you鈥檝e switched on the fan and are holding the cart still. When you remove your hand from the cart, it begins to travel ahead in a clockwise direction (+x). Once you've covered a significant distance, you swiftly halt and hold the cart. The fourth graph satisfies the above condition in which the cart is at still position,

reaches the maximum acceleration and then decreases slowly.

In the third experiment, you've had the fan facing the "wrong" direction and the cart isn't moving. Give it a fast push and the cart drives ahead, in the direction of the +x axis, before slowing down and finally turning around and returning towards the starting location. The first graph depicts the situation correctly here the cart starts from rest and accelerates with a positive acceleration then goes to rest and again takes the initial position.

Thus, the graphs are identified according to the situations given in the experiment.