- #1
Sundown444
- 179
- 7
As I have heard, for a moving object, stopping distance is proportional to the square of the speed. Is this true, and does this apply to angular movements such as body part movements?
Yes, given a fixed deceleration rate, stopping distance is proportional to the square of the starting speed. It makes sense that this should be so. It takes twice as long to slow down and during the slowdown interval, it is moving twice as fast.Sundown444 said:As I have heard, for a moving object, stopping distance is proportional to the square of the speed. Is this true, and does this apply to angular movements such as body part movements?
jbriggs444 said:Yes, given a fixed deceleration rate, stopping distance is proportional to the square of the starting speed. It makes sense that this should be so. It takes twice as long to slow down and during the slowdown interval, it is moving twice as fast.
Yes, for a fixed angular deceleration rate, the angle traversed during the slowdown is proportional to the square of the starting rotation rate. The same reasoning applies.
Of course, the deceleration rate is not always going to be equal. No matter how fast you swing your fist, it will usually stay attached to the end of your arm. Your muscles, tendons and ligaments will apply whatever force they are able to preserve that situation. Swinging twice as fast will not work to strike a fellow standing on the opposite side of the boxing ring.
Yes. Like a woman's softball pitcher?Sundown444 said:So, stopping distance applies to swinging your arms in a circular fashion at some speed as well?
jbriggs444 said:Yes. Like a woman's softball pitcher?
You could be in trouble with the sexism police with that remark. But I know what you mean about male and female throwing methods. Bowling, both in Women's and Mens' cricket involves the same action (100mph+).jbriggs444 said:Yes. Like a woman's softball pitcher?
Yes, the Kinetic Energy is mv2/2 and the distance taken will be, in simple terms , proportional to the distance because Work (energy dissipated by brakes) is Brake Force times distance. For a constant braking force, this means distance is proportional to v2.Sundown444 said:stopping distance is proportional to the square of the speed.
What does this question mean? If something is moving over here and comes to a stop over there, you can take the distance between here and there as the stopping distance. In this sense, "stopping distance" applies to anything, including projectiles.Sundown444 said:So, one other thing: does stopping distance apply to anything, including projectiles?
jbriggs444 said:What does this question mean? If something is moving over here and comes to a stop over there, you can take the distance between here and there as the stopping distance. In this sense, "stopping distance" applies to anything, including projectiles.
If you mean to ask whether stopping distance always goes as the square of starting velocity, the answer is no. The stopping force (and how that force varies over time) matters too.
The stopping force is whatever force is acting on the object to slow it down. Throw an object up into the air and gravity will eventually stop it; brake a car and the force between the tires and the road will eventually stop it; throw a ball into a net and the force of the net on the ball will stop it (and in this last example the stopping distance probably is not proportional to the square of the speed).Sundown444 said:So what do you mean by stopping force? What can it be?
Stopping distance is the distance that a moving object travels from the point when the brakes are applied to the point when it comes to a complete stop.
The higher the speed of an object, the longer the stopping distance will be. This is because the object has more momentum and takes longer to slow down and come to a stop.
Angular movement, also known as rotational motion, is not directly related to stopping distance. However, the rotational speed of an object can affect its linear speed, which in turn affects the stopping distance.
The main factors that affect stopping distance are speed, road conditions (such as wet or icy surfaces), and the condition of the vehicle's brakes and tires. Other factors such as the weight and size of the object and the reaction time of the driver may also play a role.
Understanding stopping distance can be useful for drivers to be aware of how much distance their vehicle will need to come to a stop in different situations. It can also help in making informed decisions about safe driving speeds and maintaining proper vehicle maintenance.