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A speaker emits a sound wave through a metallic block, with a speed of 0.42 km/s, and a frequency of 16kHz. Calculate the wavelength to 3.s.f. Describe the characteristics of a longitudinal wave.

Firstly the values should be converted into more comfortable units. 0.42km/s = 420m/s, and 16kHz = 16,000Hz. Next, use the equation wavelength = speed/frequency This gives wavelength = 420m/s over 16,000/s =...
JB
Answered by Joseph B. • Physics tutor
4507 Views

What is resistivity?

Resistivity is the measure of a materials resistance per unit area
TP
Answered by Tudor P. • Physics tutor
3079 Views

A cylindrical specimen of material with diameter 1.5x10^-4 has a breaking stress of 1.3GPa. Calculate the tensile force acting on the specimen at breaking point.

We first need to remember that stress is force over area. We can calculate the area using the diameter as the specimen is told to be cylindrical (circular cross-section). The area can be calculated using 0.2...
RM
Answered by Richard M. • Physics tutor
11687 Views

A 1000kg car accelerates from 0 to 20 m/s in 15 seconds. Calculate the acceleration of the car, the force required for this acceleration and the momentum of the car at 20 m/s.

The first part of the question, calculating the acceleration, uses the fact that acceleration equals the change in velocity divided by the time. In this case, the change in velocity is 20-0 and the time is 1...
RM
Answered by Richard M. • Physics tutor
5331 Views

A 100kg weight is placed 0.75 meters from a see-saw on the right hand side. Dan is 75kg. How far away does he have to sit from the pivot on the left hand side to have it balance?

A see-saw represents a pivot, for the see-saw to balance the moment on the left hand side has to equal the moment on the right hand side. Moment = Force * distance Therefore the moment of the right hand side...
AC
Answered by Alex C. • Physics tutor
2983 Views