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A 100g mass is on a circular turntable spinning at 78 revolutions per minute. The maximum frictional force between the mass and turntable is 0.50N. Find the maximum distance from the center of the turntable at which the mass would stay on the turntable.

First, draw a diagram as it makes the problem easier to understand. Show the turntable and mass. Label the distance between the mass and the centre of the turntable r as it is a radius. write down all variab...
AC
Answered by Amy C. • Physics tutor
6203 Views

The braking distance of a road train travelling at 15m/s is 70m. Assuming that the same braking force is applied at all speeds, show that the braking distance of a road train when travelling at 25m/s is about 190m.

Energy = force x distance and Energy = 0.5 x mass x velocity squared Hence, force = (0.5 x mass x velocity squared) / distance --- (equation 1) This applies for both situation A and B, and given that force i...
JJ
Answered by Jack J. • Physics tutor
10831 Views

How do I differentiate a trigonometric function for something that is not just a single variable (e.g. d/dx (sin(3x))?

In order to differentiate a trig function with a term in front of the variable you are differentiating, you must use the chain rule. For example d/dx (sin (3x)) becomes 3cos(3x) because you have to multiply ...
KT
Answered by Kieran T. • Maths tutor
5313 Views

Discuss pricing and non-pricing strategies

There are a number of pricing and non pricing a firm may use in order to seize market share, increase its total revenue and hence profits. Some pricing methods involve, a reduction in prices, predatory prici...
AP
25459 Views

What is De Moivre's theorem?

De Moivres theorem states that e^j(theta) = cos (theta) +jsin (theta) and this can be used to convert powered trig functions to the form of regular sines and cosines (i.e. sin^3(x) into a sum of terms includ...
KT
Answered by Kieran T. • Maths tutor
5716 Views