long enough
Momentum is the product of mass and velocity. When an object slows down, the object reduces in velocity. Since Mass is constant, when velocity reduces momentum reduces. thus momentum can be what stops a rolling object. However, a resistive force the reason for the reduction of velocity and subsequently halting.
Consider the gravitational pull of the earth and acceleration due to gravity. When you throw a ball in the air, at the highest point, it is stopped and has a velocity of 0. However, if the acceleration of the ball was also 0, then the ball would not be able to come back down to the earth. In order for the ball to come back down, there must be an acceleration. This acceleration is the acceleration due to gravity which is constant at the surface of the earth at 9.8 m/s^2. Another example: Say a car is rolling down a hill backwards. In order to stop the car from rolling more, the driver accelerates. After a certain amount of time, the car will stop (with velocity of 0) and then it will start moving up the hill again. When it is stopped, the car is still accelerating in order to overcome the force of gravity pulling the car down the hill.Technically, an object is accelerating if it's changing it's velocity. This includes speeding up, slowing down, and turning. So, yeah, if an object isn't moving at all, but is turning, it's still accelerrating.
The cart will move at a constant velocity.
The cart will move at a constant velocity.
Let's review some terms before we tackle this one. Speed is displacement per unit of time. We know 60 miles per hour is a speed. Velocity is speed with a direction vector associated with it. We know 60 miles per hour east is velocity. Acceleration is a change in velocity. That means if an object changes its speed or its direction or both, it is accelerating.If an object has a given velocity and it slows down or speeds up, it is accelerated. But if the same object changes direction without a change in speed, it is still experiencing acceleration. A force had to act on the object to change its direction, even though its speed didn't change. Thus, an object can accelerate even though it does not change speed.
-- a car on cruise control rolling along at a constant speed on a straight section of highway -- a golf ball or squash ball rolling across the gym floor at a constant speed
The net force will be zero only if the velocity is constant, which means acceleration is zero.
It just does, in the absence of other forces ( ie air and rolling resistance ), that is to say under ideal conditions, a constant force on a fixed mass will produce uniform acceleration (velocity change) acceleration ( (m/s)/s ) = force (newtons) / mass (kg)
Momentum is the product of mass and velocity. When an object slows down, the object reduces in velocity. Since Mass is constant, when velocity reduces momentum reduces. thus momentum can be what stops a rolling object. However, a resistive force the reason for the reduction of velocity and subsequently halting.
Consider the gravitational pull of the earth and acceleration due to gravity. When you throw a ball in the air, at the highest point, it is stopped and has a velocity of 0. However, if the acceleration of the ball was also 0, then the ball would not be able to come back down to the earth. In order for the ball to come back down, there must be an acceleration. This acceleration is the acceleration due to gravity which is constant at the surface of the earth at 9.8 m/s^2. Another example: Say a car is rolling down a hill backwards. In order to stop the car from rolling more, the driver accelerates. After a certain amount of time, the car will stop (with velocity of 0) and then it will start moving up the hill again. When it is stopped, the car is still accelerating in order to overcome the force of gravity pulling the car down the hill.Technically, an object is accelerating if it's changing it's velocity. This includes speeding up, slowing down, and turning. So, yeah, if an object isn't moving at all, but is turning, it's still accelerrating.
The cart will move at a constant velocity.
The cart will move at a constant velocity.
Let's review some terms before we tackle this one. Speed is displacement per unit of time. We know 60 miles per hour is a speed. Velocity is speed with a direction vector associated with it. We know 60 miles per hour east is velocity. Acceleration is a change in velocity. That means if an object changes its speed or its direction or both, it is accelerating.If an object has a given velocity and it slows down or speeds up, it is accelerated. But if the same object changes direction without a change in speed, it is still experiencing acceleration. A force had to act on the object to change its direction, even though its speed didn't change. Thus, an object can accelerate even though it does not change speed.
The earth is in orbit about the sun. It plods along in its orbit at close to 30 kilometers per second. But it is not moving in a straight line, as you know. It is following the curve of its orbital path. Earth's inertia and the gravitational attraction between the sun and the Earth are in equilibrium here, and though its speed is constant, its direction of travel is actually changing from moment to moment. That means its velocity is constantly changing. (Note that the actual speed of earth varies a bit through its orbit, but from moment to moment, the change of speed is miniscule.)Speed is distance (displacement) per unit of time. In this case, we have 30 km/sec for the earth. But when we consider velocity, we find that velocity is speed plus a direction vector. Though the speed of the earth is constant in its orbit, it is constantly changing direction and following its orbital path. Earth has a constant speed in its orbit, but its velocity is constantly changing because the direction it is traveling changes from moment to moment.
if you increase the force , the mass remaining constant, a new rate of acceleration applies in the order a = f/m from that point (second law)
Motion with constant velocity is motion without acceleration. That is, there is no force being applied to the object in motion. One could argue that the acceleration is constant in that case, but the constant value is zero. Now, general relativity tells us that gravity and acceleration are indistinguishable from each other for a point mass being affected by either (meaning that if you're accelerating, you cannot tell just by the effect of the force whether it's due to an actual force, F=ma, or another massive object causing gravitational attraction). So in some ways, one could argue that the force of gravity is identical to constant acceleration. The difference is that gravity is caused by the presence of mass which "warps" space-time, so the acceleration felt is actually caused not by a force acting directly on the object, but the object is moving at a "constant velocity" in the equivalent flat (non-warped) space-time, and due to the presence of another mass causing a gravitational attraction, acceleration is felt. Think of it as standing on the center of a mattress. Your weight causes the middle of the mattress to push down, and if you had something like a basketball sitting in the corner of the mattress, it would begin rolling toward you. In that example, the mattress is space-time, the basketball the body in motion, and you the mass causing gravitational attraction. In that sense, since the object would be moving at a constant velocity in a flat space-time (like the ball sitting still on the mattress), warping space-time does not apply a true force to the ball, the causes it to appear to accelerate nonetheless. This appearance is due not to a force acting directly on the ball, but acting on the space-time in which it inhabits.
The acceleration of the ball can be easily found using the kinematic equation if = vi + at. Where vi = initial velocity, if = final velocity, a = acceleration, and t = seconds. The acceleration is -0.1 m/s^2.