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What is the difference between a scalar and a vector? Give 3 examples of each.

A scalar is a quantity that has only magnitude (size) E.G Distance, Speed, Temperature A vector is a quantity that has magnitude and a direction. E.G Displacement, Velocity, Change in Temperature.
MK
Answered by Marcin K. • Physics tutor
3927 Views

An electron falling from one energy level to another emits a photon of wavelength 550nm. What is the difference between the two energy levels?

The key equation is that of the energy of a photon. E = hc/ λ​ Using λ​ = 550nm gives E = 3.61x10^-19J (Remember that a nanometer is 1x10^-9 m ). Using the conservation of energy, the energy of this photon m...
JL
Answered by Jamie L. • Physics tutor
3687 Views

A space probe of mass 1000kg, moving at 200m/s, explosively ejects a capsule of mass 300kg. The speed of the probe after the explosion is 250m/s. What is the velocity of the capsule?

To solve this problem, we must apply conservation of momentum. Even though there is kinetic energy being added to the probe-capsule system by the explosion, momentum will always be conserved if there are no ...
AS
Answered by Alexander S. • Physics tutor
8055 Views

How does energy flow from voltage source to resistor in a simple DC circuit?

Let us consider a simple dc circuit consisting of a battery and a resistor connected by ideal wires. As we know, current starts to flow thorugh the resistor and heat is generated as a result of this current ...
SH
3383 Views

If one proton is travelling through space at 0.3c, what is it's kinetic energy in MeV?

We know the formula for kinetic energy is KE = (1/2)mv 2 . If we know that c, the speed of light, is 3x10 8 ms -1 (you will be given this value in your Data & Formula books in the exam) and the proton is...
OB
Answered by Oisin B. • Physics tutor
7289 Views