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A ball is launched upwards at 30 degrees to horizontal with a velocity of 20 metres per second, how far does it travel before landing? (no air resistance)

Vertcal component of velocity: 20Sin(30) Rearrange suvat equation for t in terms of u, a, s t is the time in the air and is what we want, u is 20sin(30), a is -9.81 (negative since gravity pulls the ball dow...
JF
Answered by Joseph F. • Physics tutor
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Two immobile point charges Q1 and Q2 of values +q and +3q respectively are some distance apart. Q3, with value +2q is placed between them and does not move. What is the ratio of the distance between Q3 and Q2 to the distance between Q1 and Q3?

As Q 3 remains stationary, it is clear that it is not accelerating. Thus we can deduce from Newton's second law that there is no resultant force acting upon the charge. However there are still electrostatic ...
HR
Answered by Hugh R. • Physics tutor
4718 Views

Newton's Law of Gravitation states: F=GMm/r^2, where G is the gravitational constant (6.67×10−11m^3kg^−1s^−2). Kepler's Third Law, states t^2=kR^3. The mass of the sun is 1.99x10^30kg. Find the value of k and its units

F=GMm/r 2 =mv 2 /r, v=2pir/t equating the two values for F and remembering to include the equation for v, GMm/r^2 = m(2pir/t ^2)^2/r. Rearranging to find t^2, t^2 = 4pi^2r^3/GM where 4pi^2/GM equals the cons...
SB
Answered by Sam B. • Physics tutor
17856 Views

Derive the kinetic theory equation pV=Nm/3(crms2) for an ideal gas.

Assume a point molecule in a container with dimensions l x by l y by l z travelling at velocity c 1 given by c 1 2 =u 1 2 +v 1 2 +w 1 2 ​​​​​​ where u, v, w are the x, y, and z velocity components. >each ...
MV
Answered by Maryna V. • Physics tutor
8918 Views

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 -10 m
JG
Answered by Jozefina G. • Physics tutor
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