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A car horn has a frequency of 680 Hz and a wavelength of 50cm. Calculate the speed of the sound waves produced by the car horn:

velocity (v) = frequency of the wave (f) x wavelength of wave (in metres) (λ) 50cm in metres: 50/100 = 0.5m Therefore (v) = 680 x 0.5= 340 (m/s)
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Answered by Gunchit S. • Physics tutor
4912 Views

Calculate the kinetic energy of a car of mass 1.0*10^3kg moving at speed of 20ms^-1.

By using the equation: Kinetic Energy = (1/2)mv^2, using m as 1000kg and v as 20ms^-1.We can calculate this value as follows: KE = (1/2)(1000)(20)^2This is equal to 2.0*10^5J (solved using a scientific calcu...
RH
Answered by Robin H. • Physics tutor
9598 Views

Why is an object moving in a circle at a constant speed said to be accelerating?

First of all, it is important to remember that an object's acceleration is the rate of change of its velocity, not its speed. Velocity is a vector quantity and so must have a direction as well as a magnitude...
SG
Answered by Sam G. • Physics tutor
18676 Views

A mobile phone falls to the floor. The glass screen shatters while the aluminium frame remains intact. Explain why this happens in terms of the properties of glass and aluminium.

The glass screen is a brittle material so breaks with little plastic deformation.The aluminium material however shows elastic behavior and will, when the force is removed return to the original shape. This i...
LC
Answered by Lewis C. • Physics tutor
3427 Views

Explain how an acceleration-displacement graph could be used to determine the frequency of oscillation of a metal plate.

Acceleration (A)= Angular Velocity 2 (w 2 ) Displacement (x)Angular Displacement= 2pi Frequency (f)Gradient= A/x = w 2 = [2pi*f] 2 Rearrange the equation to get - f= (sqrt)gradient/ 2pi
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Answered by Tise O. • Physics tutor
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