## Calculating Velocity

904901860
Posts: 24
Joined: Mon Jan 08, 2018 8:16 am

### Calculating Velocity

This is the equation you would use for this correct? because p= mv?

Ana Pedreros
Posts: 62
Joined: Fri Sep 28, 2018 12:19 am

### Re: Calculating Velocity

yes and you could also use ke=1/2mv^2

davidryan3f
Posts: 63
Joined: Fri Sep 28, 2018 12:23 am

### Re: Calculating Velocity

yes, the two equations involving velocity are p=mv and KE= 1/2mv^2

Alli Hinmon 3E
Posts: 30
Joined: Wed Nov 08, 2017 3:00 am

### Re: Calculating Velocity

Make sure you know the Difference!!!
p=mv is for the velocity of a photon, he will usually give you the momentum.

Ke is for Electrons!

Lynsea_Southwick_2K
Posts: 55
Joined: Fri Sep 28, 2018 12:25 am

### Re: Calculating Velocity

What is the units for momentum, p?

805169754
Posts: 61
Joined: Fri Sep 28, 2018 12:19 am

### Re: Calculating Velocity

Lynsea_Southwick_3F wrote:What is the units for momentum, p?
If the mass is in kilograms and the velocity is in meters per second then the momentum is in kilogram meters per second (kg⋅m/s)

205458163
Posts: 33
Joined: Wed Jun 26, 2019 12:15 am

### Re: Calculating Velocity

Most of the time we use 1/2mv^2 to calculate velocity.

George_Zhu
Posts: 29
Joined: Mon Jun 17, 2019 7:23 am

### Re: Calculating Velocity

It depends on different condition, like if you need to calculate the velocity, and you have time and distance, you can use the most common equation:v=s/t, and if you have the momentum and mass of a subject, and you need to calculate the velocity, you can use the equation you have mentioned.

Brian Kwak 1D
Posts: 88
Joined: Fri Sep 28, 2018 12:17 am

### Re: Calculating Velocity

Depends on the know information you have. If you know the kinetic energy of an electron then you could use 1/2mv^2 or if you know the momentum of the electron then you could use p=mv. Also the units for momentum would be kg.m.s^-1.

Yen Ho Chou 1D
Posts: 28
Joined: Wed Feb 27, 2019 12:16 am

### Re: Calculating Velocity

electrons use ke, photons use the momentum equation