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What is the difference between speed and velocity?

The difference is a bit subtle. Velocity is speed in a particular direction. So, for example, a car travelling at 50 miles per hour round a bend is travelling at constant speed. Its direction is changing, ho...
JK
Answered by Jan K. • Physics tutor
4468 Views

Describe and explain the first stages of the life cycle of a star before it reaches the main sequence.

The star begins as a stellar nebulae. This is a dense cloud of gas and dust containing hydrogen and helium. As it is under a large amount of gravitational pressure, this nebula will then collapse under gravi...
LB
Answered by Laura B. • Physics tutor
8562 Views

The vehicle accelerates horizontally from rest to 27.8 m s–1 in a time of 4.6 s. The mass of the vehicle is 360 kg and the rider has a mass of 82 kg. 1. Calculate the average acceleration during the 4.6 s time interval.

This question is testing your ability to recognise which equations to use from the formula sheet based on the variables provided. To start, write down the known variables in the SUVAT fromat: S (distance tra...
ZA
Answered by Zaid A. • Physics tutor
8087 Views

State 2 factors that affect the centripetal force for a object having a circular path.

Answer: Can be any 2 of mass, velocity or radius of path. The formula for the centripetal force (resultant) acting F=m(v^2)/r. Therefore the variables are mass, velocity for the object and the radius of the ...
WM
Answered by Winston M. • Physics tutor
16570 Views

A 0.20 kg mass is whirled round in a vertical circle on the end of a light string of length 0.90 m. At the top point of the circle the speed of the mass is 8.2 m/s. What is the tension in the string at this point?

A diagram would be very beneficial for this problem. We can draw a free body force diagram of the mass. At the top of the circle the two forces acting on it are its weight and tension from the string. Both a...
TC
Answered by Thomas C. • Physics tutor
50796 Views