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Calculate the length of a 120m (as measured by the astronaut) spaceship travelling at 0.85c as measured by a stationary observer

The length of the spaceship of 120m was measured at rest relative to the spaceship so we will take that as the proper length, dennoted L proper We first calculate the Lorentz factor: Ɣ = 1/sqrt(1-(v/c) 2 ) Ɣ...
KM
Answered by Kerr M. • Physics tutor
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A student is measuring the acceleration due to gravity, g. They drop a piece of card from rest, from a vertical height of 0.75m above a light gate. The light gate measures the card's speed as it passes to be 3.84 m/s. Calculate an estimate for g.

This question is simply a matter of finding and applying the correct equation of motion. First, draw a diagram - even if the situation in the questions seems really simple, it's always useful to draw a diagr...
PM
Answered by Philippa M. • Physics tutor
8319 Views

A supertanker of mass 4.0 × 10^8 kg, cruising at an initial speed of 4.5 m s^(–1), takes one hour to come to rest. Assume the force slowing down the tanker is constant.

From newton's first law, an object remains in its inertial frame until a force acts upon it. This means that according to a stationary observer, the object will remain at rest or continue moving at the same ...
JC
Answered by Jack C. • Physics tutor
11311 Views

What is the wavelength of a wave travelling at 20ms^-1 with a time period of 0.2s

v = f x lambdatherefore lamba = v/ff=1/Tf = 1/0.2 = 5Hzlambda = 20/5 = 4m
HC
Answered by Hannah C. • Physics tutor
3910 Views

A boy kicks a ball and it is accelerated uniformly from rest so that after 10 seconds it has achieved a speed of 15m/s. Find the ball's acceleration.

First, clearly set out the information we know: U=0m/s, V=15m/s, T=10s, and identify the value we are wanting to find out: A=? Check that all of these value's units are in meters and seconds only. Recall the...
EW
Answered by Emma W. • Physics tutor
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