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What's the difference between a vector and a scalar?

A scalar is a single quantity giving an "amount" of something - it only has a magnitude. For example, temperature or energy are represented by a single value. On the other hand, a vector has both m...
JC
Answered by Jasmine C. • Physics tutor
4689 Views

The speed of light is 3.0 × 10^8 m/s. The wavelength of yellow light is 5.8 × 10^−7 m. Calculate the frequency of yellow light. State the unit.

We know that frequency is 1/time, thus the unit is Hz (equal to s^-1). To calculate the frequency value, we use the equation Frequency = Wavespeed (m/s) / Wavelength (m). (This also provides a checking answe...
AH
Answered by Alister H. • Physics tutor
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Why do Physicists take multiple readings in experiments?

Taking multiple readings allows for errors (known as anomalous data points) to be spotted.For example if you were to take just one reading in an experiment and this was wrong, there would be no way of tellin...
DS
Answered by Daniel S. • Physics tutor
14903 Views

Describe one method by which the distance to stars from Earth is measured, and one modern improvement to this method which increases its accuracy.

One such method is Stellar parallax. When observing stars in the night sky, stars which are further away from Earth appear to 'move' less across the sky as the earth rotates. Using this, stellar parallax wor...
HH
Answered by Harry H. • Physics tutor
2059 Views

Assuming no friction, describe the motion of a simple pendulum released from rest at t=0 at amplitude A? Provide information about its speed and position at characteristic times during one period. [The 1D equation of motion is described by a cosine]

The displacement of the bob of mass m is given by the equation x(t)=A cos(w*t), with no phase offset as given by the boundary conditions (zero speed at t=0). By differentiating this equation twice the first ...
SA
Answered by Stefan A. • Physics tutor
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