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a bat emits sound waves with a range of wavelengths. Some of the sound waves will be diffracted by the insect. Complete the following sentences to explain why. [2 marks] Diffraction is caused by the sound waves _______________________________________

spreading out

Answered by Ralph T. • Physics tutor

3001 Views

A 950 kg car accelerates from 0 to 33 m/s in 11 seconds. a) Calculate the acceleration of the car b) Calculate the force needed to produce this acceleration c) The car claims a top speed of 110 miles/hr. Explain why there must be a top speed for any car

a) a=v-u/t

= 33/1 = 3

b) F = ma

= 950x3 = 2850

c) Friction and air resistance increases with speed, till frictional = max forward force, then force/acceleration is zero

Answered by Raina B. • Physics tutor

9160 Views

What is the difference between EMF and Voltage?

EMF stands for the Electromotive Force and it can be defined in a few ways:

1. It's the potential across the terminal ends of a cell.

2. Or...

Answered by Francisco G. • Physics tutor

1445 Views

What actually is current? Why does it differ from potential difference?

Current is defined as 'the flow of electric charge'. It can be broken down into very simple system of electrons, who carry charge, moving around a circuit. Potential difference can be thought of the force...

Answered by James O. • Physics tutor

4579 Views

I dont really understand the Rutherford experiment

Rutherford revolutionised the atomic model with this experiment. At that time, the general idea was that of JJ Thompson, the "plum pudding" atomic model. Rutherford bombarded a sheet of gold wi...

Answered by Eduardo S. • Physics tutor

2769 Views