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On a see-saw Mary, weight 600N balances John, weight 200N when she sits 1.5m away from the pivot. How far from the pivot is John?

Using the knowledge that the moments are balanced, we can create an equation to calculate the distance John is from the pivot:

600N1.50m = 200N(distance)
(600/200)*1.5 = di...

Answered by Alexander N. • Physics tutor

11950 Views

The loudspeaker produces a sound wave with a frequency of 850 hertz and a wavelength of 0.4 metres. Calculate the speed of this sound wave. Give the unit

The speed of a wave is given by "Frequency*Wavelength=Wave speed". Hence, the speed is 340. With the units of speed being m/s

Answered by Alexander N. • Physics tutor

9872 Views

Describe the photoelectric effect and what it tells us about the properties of light .

The photoelectric effect describes the process by which surface electrons are emitted from a metal when light is shined on it. This occurs because the electrons are able to absorb the electromagnetic e...

Answered by Lorenzo C. • Physics tutor

14646 Views

A cup of tea contains 175 g of water at a temperature of 85.0 °C. Milk at a temperature of 4.5 °C is added to the tea and the temperature of the mixture becomes 74.0 °C. What is the internal energy lost by the water? What is the mass of the milk?

(a) In a question like this, you will be given that the Specific Heat Capacity of water is 4200Jkg^-1K^-1. However, commiting this to memory will be helpful.

Start wit...

Answered by Nathaniel S. • Physics tutor

9507 Views

How to i calculate total resistance in a circuit?

Total resistance in a circuit depends on whether the resistors are in series or parallel since this determines which equation is to be used.In series, resistors are essentially lined up next to each other...

Answered by Matthew K. • Physics tutor

17870 Views