Answer:
mechanical
Explanation:
the energy is carried by water <3 hope this helped
Explanation:
First, we need to determine the distance traveled by the car in the first 30 minutes,
.
Notice that the unit measurement for speed, in this case, is km/hr. Thus, a unit conversion of from minutes into hours is required before proceeding with the calculation, as shown below

Now, it is known that the car traveled 40 km for the first 30 minutes. Hence, the remaining distance,
, in which the driver reduces the speed to 40km/hr is
.
Subsequently, we would also like to know the time taken for the car to reach its destination, denoted by
.
.
Finally, with all the required values at hand, the average speed of the car for the entire trip is calculated as the ratio of the change in distance over the change in time.

Therefore, the average speed of the car is 50 km/hr.
The rock strike the water with the speed of 15.78 m/sec.
The speed by which rock hit the water is calculated by the formula
v=
v=
v=15.78 m/sec
Hence, the rock strike the water with the speed of 15.78 m/sec.
The change in momentum of the car is 6000 kg m/s
Explanation:
According to the impulse theorem, the change in momentum of an object is equal to the impulse exerted on the object, therefore:

where
is the change in momentum
I is the impulse exerted
For the car in this problem, the impulse received is
I = 6000 kg m/s (in the forward direction)
Therefore, the change in momentum of the car is equal to this value:
(in the forward direction)
We can also calculate what is the new momentum of the car. In fact, the initial momentum is

And so, the new momentum is

Learn more about impulse and momentum:
brainly.com/question/9484203
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