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An electron of mass 9.11x10^(-31) is fired from an electron gun at 7x10^6 m/s. What size object will the electron need to interact with in order to diffract?

Momentum of electron=mv=6.377x10^^-24 kg m/s

λ=h/mv=6.63x10^-34/6.377x10^-24=1.039...x10^-10=1x10^-10m

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Explain, using appropriate laws of motion, why the air exerts a force on the engine in the forward direction.

This question is taken from AQA 2016 question 1 part 2, http://filestore.aqa.org.uk/sample-papers-and-mark-schemes/2016/june/AQA-74071-QP-JUN16.PDF

The force is acting on the air by the engine. By ...

Answered by William L. • Physics tutor

6618 Views

Describe the difference between reflection and refraction (assume the mediums have smooth surfaces)

Reflection: a wave hits a surface, and bounces back into the medium it was originaly in

Refraction: a wave enters a medium with a different refractive index to the original medium it was travelling...

Answered by Abigail B. • Physics tutor

2478 Views

What do you understand by simple harmonic motion?

Is the motion of a mass on a spring when it is subject to the linear elastic restoring force given by Hooke's Law. The motion is sinusoidal in time and demonstrates a single resonant frequency. There are ...

Answered by Aitor T. • Physics tutor

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Two balls with the same kinetic energy have mass of ball a = m and ball b = 2m. What is the ratio of their momentums: a/b?

We know that both balls have the same kinetic energy, so we can write E_ka = E_kb We also know that kinetic energy is given by the equation E_k = 1/2 (mv²) and mom...

Answered by Zachary R. • Physics tutor

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