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How does one calculate centripetal force?

Consider the standard equation for force, F = ma. In a centripetal system, the acceleration a is given by a = v^2/r. Plugging this in to the equation for force yields F = mv^2/r; hence to calculate centri...

Answered by Liora W. • Physics tutor

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If a 10N tension force is exerted on a steel beam (E = 200 GPa) with cross-sectional area 1cm^2, what is the stress acting on the beam? What is the change in length of the beam, if the beam is 10cm long?

F = 10NA = 1x10^-6 m^2Therefore, Stress = 10 MPaStrain = Stress / E = 10 / 200 x10^3 = 5x10^-5 delta L = strain x length = 5x10^-4 cm = 5 micrometers

Answered by Elliott M. • Physics tutor

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A ball is kicked off a cliff at a height of 20m above ground and an angle of 30 degree from the horizontal, it follows projectile motion and lands after a time t. Its velocity at the maximum height it reaches is 20m/s, how long does it take it to land?

This problem should be split into two parts, the time it takes the ball to reach its maximum point, and the time it takes it to fall to the ground from the maximum point.part 1) We can calculate the balls...

Answered by Patryk k. • Physics tutor

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A car of mass 1500kg is travelling at 10 ms-1 along a horizontal road. A brake force of 3000N brings it to rest. Calculate the deceleration of the car and the distance travelled by the car whilst decelerating.

To calculate the deceleration of the car we must re-arrange F=ma to make a the subject of the formula, a = F/m. We then put in the numbers to get, 3000/1500, to get a deceleration of 2 ms^-2.
To get...

Answered by • Physics tutor

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An ideal gas within a closed system undergoes an isothermal expansion from an initial volume of 1m^3 to 2m^3. Given that the initial pressure of the gas is 10^5 Pa, find the final pressure of the gas following the expansion.

The key word to note in this question is that the expansion is isothermal and that we have a closed system. This means that the expansion must happen at a constant temperature (isotherma...

Answered by James L. • Physics tutor

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