Answer:
, downward
Explanation:
There is only one force acting on the ball during its motion: the force of gravity, which is given by

where
m is the mass of the ball
is the acceleration of gravity (downward)
According to Newton's second law,

where F is the net force on the object and a is its acceleration. Rearranging for a,

As we said, the only force acting on the ball is gravity, so F = mg and the acceleration of the ball is:

Therefore, the ball has a constant acceleration of
downward for the entire motion.
Answer:
Sound wave is a longitudinal wave that propagates in a medium
Explanation:
<em>Part A:</em> (C) Sound wave is propagation of pressure fluctuations in a medium.
<em>Part B: </em>(C) Pressure fluctuations travel along the direction of propagation of the sound wave.
<em>Part C: </em>(A) Yes air play a role in the propagation of the human voice from one end of the lecture hall to the other.
Answer:
1400 N
Explanation:
Verá, durante el salto mortal, el piloto se mueve en una trayectoria circular y la fuerza que actúa sobre él es una fuerza centrípeta.
Sea la fuerza centrípeta F, la masa del piloto (m) = 70 Kg, el radio (r) = 500 my la velocidad (v) = 360 km / hr * 1000/3600 = 100 m / s
F = mv ^ 2 / r
F = 70 * (100) ^ 2/500
F = 1400 N
Answer:
Final Speed of Dwayne 'The Rock' Johnson = 15.812 m/s
Explanation:
Let's start out with finding the force acting downwards because of the mass of 'The Rock':
Dwayne 'The Rock' Johnson: 118kg x 9.81m/s = 1157.58 N
Now the problem also states that the kinetic friction of the desk in this problem is 370 N
Since the pulley is smooth, the weight of Dwayne Johnson being transferred fully, and pulls the desk with a force of 1157.58 N. The frictional force of the desk is resisting this motion by a force of 370 N. Subtracting both forces we get the resultant force on the desk to be: 1157.58 - 370 = 787.58 N
Now lets use F = ma to calculate for the acceleration of the desk:
787.58 = 63 x acceleration
acceleration = 12.501 m/s
Finally, we can use the motion equation:

here u = 0 m/s (since initial speed of the desk is 0)
a = 12.501 m/s
and s = 10 m
Solving this we get:


Since the desk and Mr. Dwayne Johnson are connected by a taught rope, they are travelling at the same speed. Thus, Dwayne also travels at 15.812 m/s when the desk reaches the window.