Power is the rate of energy being generated or consumed. The passengers would feel as if they are experiencing a force. For example, if a car makes a sharp right turn the passengers would tend to slide in their seats away from the center of the turn, towards the left (if they are not wearing their seat belts, that is). This force acts opposite to the direction of centripetal acceleration. The centripetal acceleration points towards the center of the arc.Ĭentrifugal force is the imaginary force an unrestrained object experiences as it moves around an arc. It would be the same sensation as if you were floating in space.Ĭentripetal acceleration is the acceleration an object experiences as it travels a certain velocity along an arc. This creates a sensation where no forces are acting on you and you feel weightless.
Gravity is pulling equally on all the particles in your body. The reason you feel weightless is because there is no force pushing against you, since you are not in contact with anything. This is the well-known form for the centripetal acceleration equation. The term d θ/d t is usually called the angular velocity, which is the rate of change of the angle θ. Now, evaluate the second derivative at θ = 0. Therefore, θ can be differentiated with respect to time. In both of the above equations the chain rule of Calculus is used and by assumption θ is a function of time. The second derivative of x with respect to time t is:ĭ 2x/dt 2 = - Rcosθ(d θ/d t) 2− Rsinθ(d 2 θ/d t 2) The first derivative of x with respect to time t is: Thus, when θ = 0, the second derivative of x with respect to time must be the centripetal acceleration. Without loss of generality, we only need to look at the equation for the x-position, since we know that centripetal acceleration points towards the center of the circle. The scientific name for this phenomenon is Archimedes Principle. As a result, the object cannot remain completely submerged and it floats. This is because the weight of the liquid displaced by the object is greater than the weight of the object (since the liquid is denser). If an object were completely immersed in a liquid denser than it, the resulting buoyant force would exceed the weight of the object. If there was no air resistance, a feather would fall at the same speed as an apple. The force of gravity is F = mg, where m is the mass of the object and g is the acceleration due to gravity.Įquating, we have mg = ma. If we look at Newton's second law, F = ma. If an object is heavier the force of gravity is greater, but since it has greater mass the acceleration is the same, so it moves at the same speed (if we neglect air resistance). See solution Solutions For High School Physics Questions Solution For Problem # 1 Why is it desirable to keep the wheels rolling on the ice without locking up?
#Physics freefall problems Patch
When a moving car encounters a patch of ice the brakes are applied. What is the velocity of the arrow immediately after release? Why is it possible to drive a nail into a piece of wood with a hammer, but it is not possible to push a nail in by hand?Īn archer pulls back 0.75 m on a bow which has a stiffness of 200 N/m. The impact force on each car is the same as hitting a solid wall at: What is the difference between energy and power? What is the difference between centripetal acceleration and centrifugal force?
#Physics freefall problems free
How come in free fall you feel weightless even though gravity is pulling down on you? (ignore air resistance when answering this question). From these equations derive the equation for centripetal acceleration. Why do objects float in liquids denser than themselves?Ī particle is moving around in a circle and its position is given in polar coordinates as x = Rcosθ, and y = Rsinθ, where R is the radius of the circle, and θ is in radians.
High School Physics Questions College and University Physics Questions Extra Challenging Physics Questions High School Physics Questions Problem # 1ĭo heavier objects fall more slowly than lighter objects? To see the questions click on the category you are interested in:
This page is a good resource for students who want good quality problems to practice with when studying for tests and exams. In addition to being challenging, these questions are fun and interesting. These questions are designed to challenge and inspire you to think about physics at a deeper level. On this page I put together a collection of physics questions to help you understand physics better.
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