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An electron is accelerated through a uniform electric field of strength, E= 20 [N/C]. Determine the speed after the the electron travels 0.5 m from rest.

E=F/Q. F= 20*(1.6910^-19)=3.3810^-18NF=ma m=9.1110-31 kgTherefore, a = 3.71 * 10^12 m/s^2Since v^2= u^2 + 2as and s= 0.5m,Then v=1.9310^6 m/s

Answered by Luke F. • Physics tutor

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Two people sit opposite each other on the edge of a rotating disk of radius, R, and negligible mass. One person has a mass of 40kg, the other of 50kg. The disk is rotating at 30 revs/min. What is the rotational kinetic energy if R=1.5m?

Rotational Kinetic Energy (KE) = (1/2) x Moment of Inertia (I) x (Angular Velocity (w) )²I=SUM(MR²) = 40 x (1.5)² + 50 x (1.5)² = 90 x (1.5)² =...

Answered by Joe S. • Physics tutor

1455 Views

What is the meaning of the term "Specific Heat Capacity"?

Specific Heat Capacity is the amount of energy required to increase the temperature of 1kg of a substance by 1 degree Kelvin/Celsius ."Specific" refers to the fact that this value is per kilogra...

Answered by Daragh M. • Physics tutor

3038 Views

calaculate the resistance if two 3 ohm resitsors are placed in series and another 3 ohm was attached in parallel

total resistance for resistors in series is the addition of the resistances therefore the two 3 ohm resisters in series totals 6 ohms resistors in parallel follow the equation : 1/R_T = 1/R_...

Answered by Brandon A. • Physics tutor

1556 Views

Light with a frequency of 200nm is shone on a sodium plate with a work function of 2.28eV and electrons start escaping the surface of the plate due to the photoelectric effect. What is the maximum kinetic energy of one of these electrons in eV?

The work function of a metal is the minimum amount of energy required for electrons to start escaping the surface. This means that if we calculate the energy of each photon from the light and subtract the...

Answered by Robert S. • Physics tutor

3158 Views