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Why does lowering the control rods in a nuclear reactor reduce the amount of energy released each second from the nuclear fuel?

The boron control rods absorb slow-moving neutrons (thermal neutrons), which means that there are less available neutrons in the reactor. Since nuclear fission requires a collison between a neutron and...

Answered by Luke C. • Physics tutor

15270 Views

A capacitor discharge circuit of time constant 45ms includes a capacitor and resistor. The capacitor has a capacitance of 18µF What is the resistance of the resistor?

This question is in one of the CIE Physics Pre-U sample papers, and if you know the definition of the time constant for a capacitor circuit (=RC), its very easy, however even if you didnt it canbe deri...

Answered by Sam C. • Physics tutor

5787 Views

Explain the different types of wave.

There are two different types of wave: longitudinal and transverse. When you hear the word "wave" you are probably thinking of a transverse wave.

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Answered by Harry C. • Physics tutor

4187 Views

A pendulum has a frequency of 0.80 Hz, calculate the periodic time of the pendulum.

You need to use the equation that relates frequency and period; period = 1/frequency

Then all you need to do is plug in the frequency to get the periodic time:

Answered by Mia V. • Physics tutor

16823 Views

What determines the acoustic impedance of a material and why is it useful in understanding ultrasound imaging?

Acoustic impedance is the density of a material multiplied by the speed of sound in the material.
Knowing these two values allows use to calculate how much of th...

Answered by David A. • Physics tutor

9522 Views