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What's the difference between distance and displacement

Distance is a scalar, meaning it only has a magnitude. Displacement is a vector, meaning that it has both magnitude and direction. For instance, distance can state that I am "x" metres away from a ...
EG
Answered by Emma G. • Physics tutor
20701 Views

What is the De Broglie wavelength of an electron given it has a kinetic energy of 1 eV? You are given the mass of an electron is 9.11x10^-31 kg and Planck's constant is 6.63x10^-34

The De Broglie wavelength equation is as follows: λ=h/p We know the value of Planck's constant h and so to calculate the wavelength all we need is the momentum, which is equal to mv. The kinetic energy is gi...
DM
Answered by David M. • Physics tutor
98267 Views

If the highest frequency a song is 10 kHz and it is encoded at 16 bits per sample what is the minimum number of bytes needed to encode the 3 minute song?

The key to this question is to remember the Nyquist rate of a signal. This is the lowest sample rate which can be used for a signal without losing valid frequencies or gaining incorrect frequencies. This is ...
DM
Answered by David M. • Physics tutor
7110 Views

When red light is shone on a metal, regardless of the intensity of this light, no current will flow. However if blue light is shone on this metal a current will flow. Why does this occur?

This problem can be solved by first considering the energy of a photon e = hf. ​A photon of red light lacks the sufficient energy to free an electron. However a photon of blue light has a higher frequency an...
JP
Answered by Jonathan P. • Physics tutor
7089 Views

What is the difference between A.C. and D.C.?

A.C. stands for alternating current, and the current constantly changes direction. D.C. stands for direct current, and the current only flows in one direction.
SS
Answered by Sophie S. • Physics tutor
5624 Views