Vehicles without shock absorbers will harm the body due to this reason.Ĥ. The shock absorber prolongs the period of transfer of force on to the body of the rider. When there is a bump on the road, a sudden force is transferred to the vehicle. The shock absorbers in two wheelers play the same role as airbags in the car. To prevent this fatal shock, cars are designed with air bags in such a way that when the car meets with an accident, the momentum of the passengers will reduce slowly so that the average force acting on them will be smaller.ģ. This is very dangerous for the passengers inside the car since they will experience a large force. When a car meets with an accident, its momentum reduces drastically in a very short time. To avoid getting hurt, the player brings the ball to rest slowly.Ģ.
Due to this large average force, the hands will get hurt. So the average force acting on the body will be very large. It means that the momentum of the ball is brought to rest very quickly. If he stops his hands soon after catching the ball, the ball comes to rest very quickly. When a cricket player catches the ball, he pulls his hands gradually in the direction of the ball’s motion. The graphical representation of constant force impulse and variable force impulse is given in Figure 3.21.ġ. Since ∆ p is change in momentum of the object and is equal to impulse (J), we have The impulse can also be written in terms of the average force. Whenever the momentum of the body changes very quickly, the average force becomes larger. The average force acted on the object over the short interval of time is defined byįrom equation (3.25), the average force that act on the object is greater if ∆ t is smaller. If the force is constant over the time interval, thenĮquation (3.24) is called the ‘impulse-momentum equation’.įor a constant force, the impulse is denoted as J = F∆ t and it is also equal to change in momentum ( ∆ p ) of the object over the time interval ∆ t. Integrating over time from an initial time t i to a final time t f , we get If a force (F) acts on the object in a very short interval of time ( ∆ t ), from Newton’s second law in magnitude form This is important to know because it is an object’s kinetic energy that describes things like how long it will take to stop and how much damage it will do in a collision.If a very large force acts on an object for a very short duration, then the force is called impulsive force or impulse. An object’s Kinetic Energy is determined by half of its mass times the square of its velocity:īecause the velocity is squared (times itself again), an object that is moving 100 miles per hours has 4 times as much kinetic energy as an object that is only moving 50 miles per hour. What momentum doesn’t help determine is how much energy is contained in the movement of an object. In fact, an impulse results in a change in momentum: An impulse applied to an object gives it momentum. If you push with 10 pounds of force for 10 seconds, or push with 100 pounds of force for 1 second, the speed it will end up moving with will be the same. A force applied for an amount of time is called an impulse: Changing the motion of an object requires a force to be applied for a certain amount of time. Momentum is a measure of how much movement an object has, and knowing an object’s momentum can help you determine how much force it will take to stop or change the direction of a moving object. The combination of mass and velocity is called momentum:
In addition, the more mass an object has, the harder it is to stop. The more velocity it has, the more force it takes to stop. Once an object is moving, it takes some force to stop it or change its motion.
An object’s mass determines how much inertia it has. An object’s tendency to keep doing whatever it is doing is called inertia. If an object is moving, it will keep moving at the same speed in the same direction forever unless a new force changes or stops its motion. If the object is not moving, it will stay in place. Forces change an object’s motion, but without them, an object will keep doing whatever it was doing.
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