Atennis ball is thrown straight up with an initial speed of 20.5 m/s. it is caught at the same distance about ground as it is thrown.

21.4 m

Time in air = 2 x 2.09 = 4.18 s

Explanation:

v(f)² = v(i)² + 2as  

Take up as positive direction  

0 = 20.5² - 2 * 9.8s  

s = 21.4 m  

So the ball rises to 21.4 m  

(b) v(f) = v(i) + at  

0 = 20.5 - 9.8t  

t = 2.09 s [this is the time to max height]  

Because the ball returns to exactly the same height from which it was thrown, time up = time down  

So time in the air = 2 x 2.09 = 4.18 s

gravititional force is a force that is acting around you, it is non-contactable and it is a force that pulls you to the core of the earth.

brainliest

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: