Calculating Magnetic Force: Equations for Moving Charges at Right Angles

AI Thread Summary
A 3.60 mC charge moving at 862 m/s at right angles to a magnetic field experiences a magnetic force of 0.00425 N, leading to a calculated magnetic field strength of 1.37 T. For a second charge of 53.0 mC moving at 1300 m/s at a 55-degree angle to the magnetic field, the magnetic force is calculated using the corrected equation, yielding a force of 37.8 N. The discussion highlights that the equation F = qvB applies specifically for right angles, while a different approach using the cross-product is necessary for other angles. Clarification was needed regarding the angle measurement, confirming it was indeed 55 degrees. The calculations and understanding of magnetic force in relation to charge movement and angles were the main focus of the discussion.
camel-man
Messages
76
Reaction score
0
A 3.60 mC charge moving at 862 m/s travels at right angles to a magnetic field, and experiences a .00425 N magnetic force.

Find the strength of the magnetic field.

F = qvB (not sure if the right angle makes a difference in the equation.)

B= .00425 /(3.60x10^-6)(862) = 1.37 T

A 53.0 mC charge is now moving at 1300 m/s and 550 to the same magnetic field.

Find the magnetic force exerted on the second charge.

F = (53x10^-6C) (1300m/s)(550T) = 37.8 N

Does this look correct? Also, I am wondering what if the angle was not a right angle? how would that differ the equation I would use..
 
Physics news on Phys.org
F = qvB is true for a right angle between motion and magnetic field only, otherwise you need the cross-product of velocity and magnetic field.

A 53.0 mC charge is now moving at 1300 m/s and 550 to the same magnetic field.
And 550 what? Is that an angle? 55°?
F = (53x10^-6C) (1300m/s)(550T) = 37.8 N
The problem statement said you should use the magnetic field from the first subquestion. And 550T is not a reasonable field strength.
 
Ahh yes I'm sorry I copy and pasted it over and didn't realize it put a zero. It is 55 degrees. yes.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top