Time taken by proton to complete one complete circular orbit= 7.28 x 10⁻⁸ s
Explanation:
For proton, the centripetal force required for circular motion is provided by the magnetic force,
so Fm= Fc
q v B = m v²/r
m= mass of charged particle
v= velocity
B =magnetic field
q= charge
r= radius of circular path
v= q B r/m
now v= r ω
ω= angular velocity
ω r = q B r /m
ω=q B /m
now ω= 2π/T where T =time period
so 2π/T=q B/m
T= 2 πm/q B
T= 2π (1.67 x 10⁻²⁷)/ [( 1.6 x 10⁻¹⁹)* (0.9)]
T= 7.28 x 10⁻⁸ s
Magnetic field direction is given by right hand thumb rule.
If we put our thumb in the direction of current then curl of fingers will show the magnetic field direction around the wire.
Now here since current is going into the screen so we will put our thumb into the screen and then the curl of fingers is clockwise around it.
The magnetic field is clockwise.
So this would be the direction of magnetic field
Answer:
60 m/s
Explanation:
From the law of conservation of energy,
The kinetic energy of the plane = Energy of store in the spring when the plane lands.
1/2mv² = 1/2ke²
making v the subject of the equation.
v = √(ke²/m).................... Equation 1
Where v = the plane landing speed, k = spring constant, e = extension. m = mass of the plane.
Given: m = 15000 kg, k = 60000 N/m, e = 30 m.
Substitute into equation 1
v = √(60000×30²/15000)
v = √(4×900)
v = √(3600)
v = 60 m/s.
Hence the plane's landing speed = 60 m/s
Answer:
The magnetic field through the wire must be changing
Explanation:
According to Faraday's law, the induced emf, ε in a metallic conductor is directly proportional to the rate of change of magnetic flux,Φ through it. This is stated mathematically as ε = dΦ/dt.
Now for the wire, the magnetic flux through it is given by Φ = ABcosθ where A = cross-sectional area of wire, B = magnetic field and θ = angle between A and B.
So, dΦ/dt = dABcosθ/dt
Since A and B are constant,
dΦ/dt = ABdcosθ/dt = -(dθ/dt)ABsinθ
Since dθ/dt implies a change in the angle between A and B, since A is constant, it implies that B must be rotating.
So, <u>for an electric current (or voltage) to be produced in the wire, the magnetic field must be rotating or changing</u>.
Answer:
No, the sound produced by screeching brakes is not a useful form of energy, because it does not contribute to stopping the car.
