An automobile has a vertical radio antenna 1.40 m long. The automobile travels at 56.0 km/h on a horizontal road where Earth's magnetic field is 50.0 µT, directed toward the north and downward at an angle of 65.0° below the horizontal.

Calculate the magnitude of this induced emf.

...........MV

How is the speed of an object in space measured? Also more importantly how do you measure your own speed in space? On the road we use a speedometer which tells us the speed easily. How is it done in space?

a) Describe how a circular turn (or a circular coil) constitutes a dipole magnet.

b) Consider a solenoid of N turns with a radius r and length l, and carrying a current I. What is the magnitude of magnetic field inside the solenoid (but not near the ends)? Does this magnitude depend on distance the center of the solenoid? ?

c) What is the magnitude of magnetic field outside the solenoid (but not near the ends)?

Discuss the main differences of direct gap and indirect gap semi-conductors.

A constant force is applied to an object, causing the object to accelerate at 6.0 m/s^2?

A. What will the acceleration be if the force is halved?

B.What will the acceleration be if the object's mass is halved?

C. What will the acceleration be if the force and the object's mass are both halved?

D. What will the acceleration be if the force is halved and the object's mass is doubled?

On a vacation flight, you look out the window of the jet and wonder about the forces exerted on the window. Suppose the air outside the window moves with a speed of approximately 150m/s shortly after takeoff, and that the air inside the plane is at atmospheric pressure.

(A) Find the pressure difference between the inside and outside of the window.

(B) If the window is 25cm by 45cm, find the force exerted on the window by air pressure.

I've heard people talk about "department store scopes" or "trash scopes". How do I know what to avoid in a beginner scope? How can I know that I'm not getting something we will be more frustrated with than excited about?

A very long, straight wire carries a current of 18.3 A out of the screen. An electron outside the wire is 1.79 cm to the right of the central axis of the wire and is moving with a speed of 5.95×10⁶ m/s.

A. Find the magnitude of the magnetic force on the electron if it is moving directly away from the wire (i.e., rightward).

B. Find the magnitude of the force on the electron if it is moving parallel to the wire in the direction of the current (i.e., out of the screen)

C.Find the magnitude of the force on the electron if it is moving upward

AFAIK all the celestial objects have a spin motion around its axis. What is the reason for this? If it must rotate by some theory, what decides it's direction and speed of rotation?

Is there any object that does not rotate about its axis?

A horizontal spring has one end fixed and one end attached to a 3 kg mass, which slides without friction. The spring has a stiffness constant of 48 N/m. At time t = 0 the mass is at rest at the origin when a driving force of F = 120 cos 6t (F is in newtons) is applied.

(a) Find the natural oscillation frequency, ω◦, and show that the homogeneous solution (i.e., the solution to the motion when F = 0 ) is xh(t) = A cos 4t + B sin 4t.

(b) Use the method of undetermined coefficients to find the particular solution. Use an initial guess of xp(t) = C cos 6t + D sin 6t, then find values for C and D. [Ans: xp(t) = −2 cos 6t]

(c) Apply the initial conditions to show that the general solution is x(t) = 2 [cos 4t − cos 6t].

(d) Use a trig identity to re-write the general solution in part (c) as x(t) = 4 sin t sin 5t

The coordinates of a bird flying in the xy plane are given by x(t)=?t and y(t)=3.0m??t2, where ?=2.4m/s and ?=1.2m/s2

Part A:

Calculate the velocity vector of the bird as a function of time.

Give your answer as a pair of components separated by a comma. For example, if you think the x component is 3t and the y component is 4t, then you should enter 3t,4t. Express your answer using two significant figures for all coefficients.

Part B:

Calculate the acceleration vector of the bird as a function of time.

Give your answer as a pair of components separated by a comma. For example, if you think the x component is 3t and the y component is 4t, then you should enter 3t,4t. Express your answer using two significant figures for all coefficients.

Part C:

Calculate the magnitude of the bird's velocity at t=2.0 s.

Express your answer using two significant figures.

Part D:

Let the direction be the angle that the vector makes with the +x axis measured counterclockwise. Calculate the direction of the bird's velocity at t=2.0 s.

Express your answer in degrees using two significant figures.

Part E:

Calculate the magnitude of the bird's acceleration at t=2.0 s.

Express your answer using two significant figures.

Part F: Calculate the direction of the bird's acceleration at t=2.0 s

Part G: At t=2.0 s, is the bird speeding up, slowing down or moving at constant speed?

A 1.14 kg hollow ball with a radius of 0.133 m, filled with air, is released from rest at depth of 2.09 m in a pool of water. (depth is to the center of ball) What is the net vertical force acting on the ball?(Neglect all frictional effects. Neglect the ball's motion when it is only partially submerged. Neglect the mass of the air in the ball.) What is the work done by the net vertical force on the ball as the ball moves from the bottom of the pool to the surface? How high above the water does the ball shoot upward?