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Person A, weighing 35 kg, is sitting 10m away from a seesaw pivot. Person B, weighing 50 kg, it sitting at the other end, at a distance d. Calculate d, in order for the seesaw not to topple over. (g=10m/s^2)

Force@A: F A = m A x g = 35 x 10 = 350NAnticlockwise moment: M A = F A x d A = 350 x 10 = 3500NmForce @B: F B =m b x g = 50 x 10 = 500NClockwise moment: M c = F B x d B For the seesaw to be in equilibrium, M...
AA
Answered by Antonia A. • Physics tutor
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How does refraction work?

The fastest light can travel is when it is in a vacuum, where it travels at 3x10^8 metres per second. However, when light travels through another substance or material (another 'medium'), it gets slowed down...
CP
Answered by Conor P. • Physics tutor
12775 Views

How do I use equations of motion ('suvat') to find a missing quantity?

First, be familiar with the equations of motion:s = displacementu = initial velocityv = final velocitya = acceleration (constant)t = time v = u + ats = ((u+v)t)/2s = ut + (at^2)/2v^2 = u^2 + 2as Second, iden...
JH
Answered by Jessica H. • Physics tutor
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why does applying the brakes of a car cause the temperature of the breaks to increase?

The increase in heat is caused by friction between the brakes and the wheels. This work done between the brakes and the wheels, causes a decrease in kinetic energy in the wheels, resulting in an increase in ...
HH
Answered by Hugo H. • Physics tutor
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Astronauts on the ISS orbit Earth 16 times a day at a height of 400km above the surface. Given that the radius of Earth is approximately 6400km, how fast are the astronauts travelling?

v = 2𝜋R/T where R is the orbital radius, T is the time period.R = radius_of_earth + height_of_orbit = 6800km + 400km = 6800km = 6.8×10 6 m.T = hours_in_day/number_of_orbits_in_day = 24/16 hours = 1.5 hours =...
PV
Answered by Paaryn V. • Physics tutor
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