Answer:
<u>because of the doppler effect</u>
Explanation:
<em>Remember</em>, the doppler effect refers to the changes in sound (frequency of sound) observed by a person who is in a position relative to the wave source.
In this example, we notice as the train comes closer to the boy, the sound becomes louder also increasing the pitch slightly, the doppler effect sets in when the train passes the boy because the boy notices a decrease in the pitch of the moving train.
We learn from the change in the observed sound of the train that the frequency of the sound is determined by the distance of the observer from the wave source.
In other words, the closer the source of the sound to the observer; the faster it travels to the observer, however, the farther it is; the lesser it is; the greater the sound heard.
The initial position of the object was found to be 134.09 m.
<u>Explanation:</u>
As displacement is the measure of difference between the final and initial points. In other words, we can say that displacement can be termed as the change in the position of the object irrespective of the path followed by the object to change the path. So
Displacement = Final position - Initial position.
As the final position is stated as -55.25 meters and the displacement is also stated as -189.34 meters. So the initial position will be
Initial position of the object = Final position-Displacement
Initial position = -55.25 m - (-189.34 m) = -55.25 m + 189.34 m = 134.09 m.
Thus, the initial position for the object having a displacement of -189.34 m is determined as 134.09 m.
Answer:
(A) The period of its rotation is 0.5 s (2) The frequency of its rotation is 2 Hz.
Explanation:
Given that,
a ball is spun around in circular motion such that it completes 50 rotations in 25 s.
(1). Let T be the period of its rotation. It can be calculated as follows :
(2). Let f be the frequency of its rotation. It can be defined as the number of rotations per unit time. So,
Hence, this is the required solution.
Answer:
The object will rotate with constant angular acceleration
Explanation:
According to the Newton's Second Law for Whenever there is more than one torque acting on a rigid body that posses fixed axis, the moment of inertia as well as the angular acceleration is equals or proportional to the summation of the torques. It gives details on the relationship between rotational kinematics and torque as well as moment of inertia. This can be represented by the below equation.
∑iτi=Iα.
.Therefore when constant net torque is applied to object that is rotating, the object will rotate with constant angular acceleration
