Answer:
1530 m/s
Explanation:
Given that :
Speed = distance / time
Travel time take = 0.2 s
Distance covered = 306 metres
The speed of sound in the material :
Speed = distance / time = 306 m / 0.2
Speed = 1530 m/s
Answer:

Explanation:
<u>Instant Velocity
</u>
Given the position as a function of time x(t), the instant velocity is the derivative of the function:

We are given the position as

The derivative of x is

A) Let's compute v(0)

B)


C)


D)


Answer:
The bubble gum experiment demonstrates the law of conservation of mass in that even though the bubble gum has lost mass, this loss in mass is not because some matter present in the gum has been destroyed, but it has changed form and has been removed from the gum.
Explanation:
In this science experiment, students investigate whether or not chewing gum should be considered eating. During the process of chewing the gum, the gum loses mass. The experiment is used to demonstrate the law of conservation of mass which states that matter can neither be created nor destroyed but may change from one form to another.
The loss in mass of the gum is due to the fact that the sugar present in the gum has changed form and has been removed from the gum. During the process of chewing the gum, the sugar in solid form present in the gum is dissolved in the saliva found in the mouth. The dissolved sugar is then swallowed and passes into the digestive tract for digestion. This shows that even though the bubble gum has lost mass, this loss in mass is not because some matter present in the gum has been destroyed, but it has changed form and has been removed from the gum, This demonstrates the law of conservation of mass.
mass of the box = 20 kg
force of friction on the box due to surface



similarly kinetic friction on it



now the weight of the suspended block will be

so here the weight of the suspended block is less than the limiting friction on it
So here we will say that friction will counter balance the weight of the suspended block and it will not move at all
So acceleration of the box will be zero
Answer:

Explanation:
= Rate at which the distance between A and starting point of B is changing = -20 km/h
= Rate at which the distance of B is changing = 15 km/h
= Rate at which the distance between A and B is changing
Time after which the rate at which the distance between A and B is changing is 4 hours
Distance covered by A in 4 hours = 
a = Distance remaining to the start point of B = 
b = Distance covered by B in 4 hours = 
Distance between A and B after 4 hours


Differentiating with respect to time we get

The rate at which the distance between the ships is changing at 4 PM is
.