Answer: 7.3seconds
Explanation:
Using the echo concept, before echo can occur, we must have an object making the sound (the teacher), the diatance between the object and the reflector (x)(i.e the wall), the time taken for the shadow to disappear (t) and the velocity of sound /movement of the object (v). Using the relationship 2x = vt
According to the question, x = 12m (initial distance), v = speed of object t = time of disappearance.
We have time before disappearance calculated as 2 × 12/1.1 = 21.8s
When he is 4m from the building, it will there take 4 × 21.8/12 = 7.3seconds for his shadow to decrease on the way.
The answer is A. Solids have both definite shape and denfinite volume.
In an Inelastic Collision , the momentum of system is conserved .
In the question ,
it is asked about what happens in inelastic collision .
The Inelastic collision is defined as a collision in which there is a loss of kinetic energy. While the momentum of system is conserved in an inelastic collision, kinetic energy is not.
That's because some kinetic energy gets transferred to something else like ⇒ thermal energy, sound energy, or material deformation .
For Example : Let the two similar trolleys are traveling towards each other and if they collide,
but the trolleys are equipped with magnetic couplers they join together in the collision and behave like a one connected mass. This collision is perfectly inelastic .
Therefore , the details about Inelastic Collision is explained above .
The given question is incomplete , the complete question is
What happens in an inelastic collision ?
Learn more about Inelastic Collision here
brainly.com/question/14521843
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