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Constant forces provide a constant speed.
This is true on a basic physics level, you could argue and bring up examples but this is PHYSICS, it doesn't deal with real life. It's all mirrors and forces.
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Why is KE equal to half mass velocity squared?
You can derive it from accelerating an object to a certain speed. Assume constant acceleration (and therefore constant force), and calculate how much work (force x distance) you need to get the object to a specific speed.
Driving along a road at a constant velocity of 100km h-1.the forces opposing the motion of the car total 800N. cars mass is 1200kg.what force do you need to maintain constant velocity?
It doesn't matter what the car's mass is, or for that matter, what speed you're talking about.If the total forces opposing its motion are 800 N, then you need to supply 800 N in the directionof motion in order to maintain a constant speed.
What force do you need to change speed?
The most basic equation in physics, which was formulated by Isaac Newton, is force equals mass times acceleration. So the amount of force that you need to change speed depends both on the mass of the object whose speed you are changing, and the amount of the change in speed.
Why does kinetic energy quadruple if speed doubles?
Work (which is a type of energy transfer) = force x distance.Look at the formulae for acceleration. The relevant formula in this case (simplified for the case that the initial speed is zero) is: Distance = (1/2) acceleration time squared Let's keep the acceleration constant. Note that this will also make the force constant. In this case, in twice the time your object will move four times the distance. Note that at constant acceleration, in twice the time you get twice the speed (assuming that you start at speed = 0). Combining all of the above, to get twice the speed, you need to apply the same acceleration (and therefore, the same force) over FOUR times the distance. As a result, the amount of work required to achieve this acceleration will also increase by a factor four. Or in general, it will scale with the square of the speed.
Why do lorries need a force to keep them moving at a steady speed?
They need the force to overcome the friction between the lorry and the road.
How do you calculate HP need to keep constant speed?
It is equal to the retarding force due to friction.
Why is KE equal to half mass velocity squared?
You can derive it from accelerating an object to a certain speed. Assume constant acceleration (and therefore constant force), and calculate how much work (force x distance) you need to get the object to a specific speed.
Why does a car need force from its engine when moving at a constant speed?
If there be no force ie no deceleration then no need to apply any force to compensate such a deceleration. But deceleration is there due to frictional force between the tyre and the road. Hence to compensate this we have apply acceleration. So force is needed OK Physics laws State that an object in motion will remain in motion until acted upon by an outside force. The car moving at a constant speed is being acted upon by wind resistance, gravity, and friction. Therefore force is needed to retain the constant speed
What state do you called an object with a net force of 0?
The object is in constant, uniform motion. It's moving in a straight line, and at a constant speed ... which may be zero but doesn't need to be.
How could you measure frictional force?
For dynamic friction, measure the force required to maintain a constant speed. If you have to pull with 300 N to maintain a constant speed, then friction is pulling back with 300 N. (If the forces were not balanced, there would be an acceleration.) For static friction, see how much force you need to apply before the object starts moving.
Driving along a road at a constant velocity of 100km h-1.the forces opposing the motion of the car total 800N. cars mass is 1200kg.what force do you need to maintain constant velocity?
It doesn't matter what the car's mass is, or for that matter, what speed you're talking about.If the total forces opposing its motion are 800 N, then you need to supply 800 N in the directionof motion in order to maintain a constant speed.
What is the magnitude of force acting on a body moving with constant velocity?
Certainly not. An object has momentum on account of its motion, which depends on its mass and its velocity. Force may be involved in the object's motion, but doesn't need to be. If we let the discussion become somewhat flabby, we can imagine a constant force applied to an object, and asked what happens to the object's momentum. An object with a constant force acting on it exhibits constant acceleration in the direction of the force. In that situation, the object's speed, and therefore its momentum, are proportional to the time the force continues to act on it.
Is speed is always constant?
It seems like you need to put more info into the question. Just think if you're talking about cars, if they were all a constant speed, the word overtaking would never need to exist
How much force is needed to move an object?
No force is needed to keep an object moving. An object with no forces on it keeps moving at a constant speed in a straight line. If there is any force acting on it to make it slow down, then you need just enough force to cancel the first one, in order to keep it moving.
Is the net force zero if the object is not moving?
Yes, but an object with net force of zero may still be moving. The net force is zero if the object is not accelerating.
What force do you need to change speed?
The most basic equation in physics, which was formulated by Isaac Newton, is force equals mass times acceleration. So the amount of force that you need to change speed depends both on the mass of the object whose speed you are changing, and the amount of the change in speed.
Does work done depends on time what you mean is doing a work in 5 minutes needs more work or doing a work in 10 minutes need more work you mean more newtons?
Newtons is used to measure force, NOT work or energy. It is important not to confuse force with energy (or work). Whether you need more force depends on the exact situation. For example: * When pulling an object in a situation where you have to overcome friction between solids, the force is practically independent of the speed. * When pulling an object through a fluid, the force does increase for a greater speed. * When pulling an object at a constant speed upwards (against the pull of gravity), the force required is independent of the speed (ignoring air resistance).
