I think is True! Is the best answer. Because the trumpet it make them sounds like the lips with the musician and it vibrate.
Answer:
(a)
(b) I =428 
(c)
Explanation:
GIVEN
mass = 18.2 kg
radial arm length = 3.81 m
velocity = 49.8 m/s
mass of arm = 22.6 kg
we know using relation between linear velocity and angular velocity


for angular acceleration, use the following equation.

since 
here for one circle is 2 π radians. therefore for one quarter of a circle is π/2 radians
so for one quarter 

on solving

(b)
For the catapult,
moment of inertia


For the ball,



so total moment of inertia = 428 
(c)


Like windmills they use the winds to generate their power.
Answer:
The elevator must be <u>accelerating upward</u> as the net force acting is upward.
Explanation:
Given:
Original weight of the student, 
Reading on the spring scale is the normal reaction by the scale on the student and is given as, 
The normal reaction acts in the upward direction while the weight of the student acts vertically downward.
Now, the magnitude of the normal reaction is greater than the magnitude of the weight. Therefore, the net force acting on the student is given as:

Therefore, the net force is acting vertically upward.
Now, as per Newton's second law, the direction of the net acceleration acting on a body is the same as the direction of the net force acting on it.
Thus, the elevator must be accelerating upward as the net force acting is upward.
Answer:
2.5km
Explanation:
Assuming you also walk with the average human walking speed of 5 km/h. We know that speed=distance/time and now making distance the subject, distance is a product of speed and time. The time is 30 minutes, expressed in hours will be 30/60=0.5 hours. Substituting 5km/h for speed and 0.5 hours for time then the diatance covered will be
Distance=5*0.5=2.5 km