Adentist causes the bit of a high-speed drill to accelerate from an angular speed of 1.50 × 10 4 1.50×104 rad/s to an angular speed of 3.35 × 10 4 3.35×104 rad/s. in the process, the bit turns through 2.02 × 10 4 2.02×104 rad. assuming a constant angular acceleration, how long would it take the bit to reach its maximum speed of 6.90 × 10 4 6.90×104 rad/s, starting from rest?

0.32 s

Explanation:

Initial angular speed:

Final angular speed:

Angular rotation:

The angular acceleration of the drill can be found by using the equation:

Re-arranging it, we find , the angular acceleration:

Now we want to know the time t the drill takes to accelerate from

to

This can be found by using the equation

where is the angular acceleration we found previously. Solving for t,

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

a electromagnetic waves