physics

One particle has a mass of 3.00*10-3 kg and a charge of +7.60 µC. A second particle has a mass of 6.00*10-3 kg and the same charge. The two particles are initially held in place and then released. The particles fly apart, and when the separation between them is 0.100 m, the speed of the 3.00*10-3 kg particle is 140 m/s. Find the initial separation between the particles.

You can so,ve this problem by using conservation of energy.

First you find the speed of the aother particle. You use the fact that momentum is conserved. It was zero when the particles were released so it's still zero.

The fact that the total mometum is zero leads to the conclusion that second particle is moving at half the speed of the first particle (and in the opposite direction), because it's mass is twice that of the first particle.

You now know the speeds of both particles and from that you can calculate the kinetic energy. From the distance of the two particles you calculate the potential energy:

q1*q2/(4 pi epsilon_0 r)

The total energy is the sum of the potential and kinetic energy. When the particles were just released they both had a velocity of zero. So at that time the total energy was the potential energy they had. But since energy is conserved that potential energy was equal to the total energy you just computed. This means that the distance r_int is such that:

q1*q2/(4 pi epsilon_0 r_int) = total energy

1. 👍 0
2. 👎 0
3. 👁 121

Similar Questions

1. Physics

A uranium nucleus (mass 238 u, charge 92e) decays, emitting an alpha particle (mass 4 u, charge 2e) and leaving a thorium nucleus (mass 234 u, charge 90e). At the instant the alpha particle leaves the nucleus, the centers of the

asked by Nguyen Nguyen on February 26, 2015
2. PARTICLE PHYSICS

particle A has a mass of 2 and a charge of -1. particle B has a mass of 2 and a charge of +1. are particle A and particle B necessarily antiparticles? explain your answer

asked by Nick on June 9, 2010
3. physics

can anyone help me in this question please A particle of mass 27 g and charge 32 µC is released from rest when it is 79 cm from a second particle of charge −22 µC. Determine the magnitude of the initial acceleration of the 27

asked by alin on January 28, 2016
4. Physics2

A particle of mass 47 g and charge 54 C is released from rest when it is 13 cm from a second particle of charge −15 C. Determine the magnitude of the initial acceleration of the 47 g particle. Answer in units of m/s2

asked by jc on February 12, 2012
5. electrostatic physics

A particle of mass 47 g and charge 54 C is released from rest when it is 13 cm from a second particle of charge −15 C. Determine the magnitude of the initial acceleration of the 47 g particle. Answer in units of m/s2

asked by jc on February 12, 2012
6. Physics

A particle of mass 57 g and charge 70 µC is released from rest when it is 34 cm from a second particle of charge −12 µC. Determine the magnitude of the initial acceleration of the 57 g particle. Answer in units of m/s2.

asked by Ayo on January 27, 2016
7. College Physics

Two equally charged particles, held 2.8 x 10-3 m apart, are released from rest. The initial acceleration of the first particle is observed to be 6.8 m/s2 and that of the second to be 6.8 m/s2. If the mass of the first particle is

asked by Stephanie6 on July 6, 2012
8. Physics

Particle A has twice the mass of particle B, and carries three times the charge of B charge. Both particles are sent perpendicularly through a uniform magnetic field, each with the same kinetic energy. What is the ratio of the

asked by Sandhya on May 23, 2009
9. physics

A particle of mass 86 g and charge 24 μC is released from rest when it is 67 cm from a second particle of charge −12 μC. Determine the magnitude of the initial ac- celeration of the 86 g particle.

asked by tt on July 8, 2010
10. Physics

Particle A has a mass of 2 and a charge of -1. Particle B has a mass of 2 and a charge of +1. Are particle A and B necessarily antiparticles? Explain your answer.

asked by Linn on April 13, 2009
11. College Physics

particle 1 of charge q1 = 1.04 ìC and particle 2 of charge q2 = -2.99 ìC, are held at separation L = 10.8 cm on an x axis. If particle 3 of unknown charge q3 is to be located such that the net electrostatic force on it from

asked by Stephanie13 on July 6, 2012

More Similar Questions