To determine the acceleration due to gravity by means of a conical pendulum

ExpConPenA student conducted an experiment to measure the acceleration of gravity. He used a conical pendulum. The conical pendulum is a string with a bob (weight) that revolves around an axis through its point of suspension.
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A block and a triangular wedge move together

Problem20_2A block of mass m and a triangular wedge of mass M move together without slipping due to a pulling force F. The triangular wedge has a slope α. There is no friction between any pair of surfaces. Derive an equation of pulling force.

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A system of three objects

3objectsNewton2LawA system is composed of three objects with masses m, 5m and 6m. The coefficient of kinetic friction between the objects m, 5m and the surface is 0.5. Find the acceleration of the objects.
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The force required to hold a water hose

Calculate the force required to hold a water hose of radius 0.04 m when it emits a jet of water at a speed of 20 m/s.

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Object, String & Elevator

An object of mass m is hanging by a string from the ceiling of an elevator. The elevator is moving upward, but slowing down.

What is the tension in the string?


a) zero
b) greater than mg
c) exactly mg
d) less than mg

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If the solar system were reduced

Solar System (artist's impression) If all the linear dimensions of the solar system were reduced in some proportion, then what will be the length of Earth’s year?


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A hockey player & referee

hockeyA 100 kg hockey player pushes a 80 kg referee with a force of 800N. Assuming they on a frictionless ice surface and the push lasts for 0.5 seconds, find the following: a) the acceleration experienced by each person b) the maximum velocity reached by each person c) do the resulting motions depend on which person instigated the pushing?   Continue reading