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From the definition of the decay constant for nuclear decay, derive the exponential decay equation.

By definition, dn/dt = - λ N , If you separate the variables which contain N and t, and then integrate w.r.t N and w.r.t t you get, lnN = -λt + C (1), To find the constant of integration, solve (1) by settin...
JP
Answered by Jake P. • Physics tutor
2958 Views

Explain the difference between elastic and inelastic collisions.

In all collisions, provided there are no external forces, momentum is conserved. This is the law of conservation of momentum. However, kinetic energy is not conserved in all collisions. An inelastic collisio...
EE
Answered by Ellie E. • Physics tutor
8066 Views

For a body of mass m orbiting a body of mass M with radius of orbit r, what is the minimum velocity that m needs in order to escape M's gravitational pull and end up infinitely far away from M?

Answer: escape velocity v = sqrt[(2GM)/r], where G is the gravitational constant. Reasoning: Conservation of energy means that the total initial energy must be equal to the total final energy, in other words...
GF
Answered by Grace F. • Physics tutor
1619 Views

How do you calculate efficiency?

The efficiency is calculated using the equation: ((Total useful output energy)/(Total input energy)) *100 We are essentially trying to calculate what percentage of the input energy is converted into a useful...
RM
Answered by Rachel M. • Physics tutor
2722 Views

A ball is thrown vertically downwards at a speed of 10ms^-1 from a height of 10m. Upon hitting the floor 10% of the energy is dissipated through waste heat. What is the heighest point the ball reaches before it comes to rest? Take g=10ms^-2

The first step is to calculate the initial energy of the system. at the moment of throwing. Energy is comprised of both potential (given by Mgh) and kinetic(given by 0.5Mv^2), and so the initial energy is : ...
RJ
Answered by Russell J. • Physics tutor
1939 Views