Mindblown: a blog about philosophy.
-
If in a coil with 2×10−3H coefficient of self-inductance, current flows for 0.1s is increased at a constant rate by 1A,then the magnitude of induced emf is:
A. 2V B. 0.02V C. 0.2V D. Zero Answer:- B. 0.02V Right option is B) Specified, L=2×10−3H Δt=0.1sec ΔI=1amp. We identify that, ∴ε=−ΔtLΔI =−2×10−3×0.11=−2×10−2 =−0.02V
-
What is the induced e.m.f. when the rate of change in magnetic flux is 6 T m^2 s–^1?
What is the induced e.m.f. when the rate of change in magnetic flux is 6 T m^2 s–^1?
-
In a mass spectrometer used for measuring the masses of ions, the ions are initially accelerated by an electric potential V and then made to describe semicircular paths of radius R using a magnetic field B. If V and B are kept constant, the ratio (Charge on the ion/Mass of the ion ) will be proportional to
A. 1/R B. 1/R2 C. R2 D. R Answer:- Right option is B) 1/R2 Let q be the charge and m be the mass of the particle. Energy is amplified only by the electric field doing work. ⇒qV=21mv2⇒v=mq 2V The magnetic field delivers receptive force for motion in circle: ⇒Rmv2=qvB ⇒v=mqBR⇒BR12V =mq ⇒mq=B2R22V ⇒mq∝R21
-
What is the relationship between magnetic field strength, mass of particle, velocity of particle, charge on particle and radius of path?
What is the relationship between magnetic field strength, mass of particle, velocity of particle, charge on particle and radius of path?
-
The magnetic force per unit length on a wire carrying a current of 10 A and making an angle of 45 degree with the direction of a uniform magnetic field of 0.20 T is
Answer:- Correct option is B) I=10A, θ=45o, B=0.2T ∴F=IlBsinθ ∴lF=IBsin45o=10×0.2×2 1=2 2Nm−1
-
What is the formula to find the force on a rectangular current-carrying coil?
a) What is the formula to find the force on a rectangular current-carrying coil? b) What is the force on a coil in a magnetic field of 0.2 T, with a current of 1 A, an area of 0.025 m2 and 100 turns?
-
A particle of mass m and charge q moves with a constant velocity v along the positive x− direction.
extending from x=a to x=b. The minimum value of v required so that the particle can just enter the region x>b is Answer:- Correct option is B) Radius of curvature has to be better than the width of magnetic field for the particle to enter the region x>B. ∴qBmv>(b−a) ⇒v>mqB(b−a) ∴vmin=mqB(b−a)
-
Calculate the magnetic field strength when a current of 3A flows in a wire 2.5m long and produce a force of 15N
Answer:- The magnetic field strength is 2N/Am The Lorentz law indicates that the force produced on a present carrying wire located in the magnetic field is the produce of its length, current and magnetic field strength. Consequently, we write F= Bil Replacing the known values in above relation, we get 15 B x 3 x…
-
Describe how you could demonstrate magnetisation of iron filings or shredded steel wool.
Describe how you could demonstrate magnetisation of iron filings or shredded steel wool.
-
Draw a circuit diagram to show a battery of two cells and three light bulbs connected in series.
Draw a circuit diagram to show a battery of two cells and three light bulbs connected in series. Include a switch to turn the lights on and off. Does it matter where the switch is placed in the circuit?
Got any book recommendations?