Answer:
I think decreases inversely
Explanation:
the third
Answer:

Explanation:
<u>Motion With Constant Acceleration
</u>
It's a type of motion in which the velocity of an object changes uniformly over time.
The equation that describes the change of velocities is:

Where:
a = acceleration
vo = initial speed
vf = final speed
t = time
Solving the equation for a:

The ball starts at rest (vo=0) and rolls down an inclined plane that makes it reach a speed of vf=7.5 m/s in t=3 seconds.
The acceleration is:


the friction force provided by the brakes is 30000 N.
<h3>What is friction force?</h3>
Friction force is the force that opposes the motion between two bodies in contact.
To calculate the average friction force provided by the brakes, we apply the formula below.
Formula:
- K.E = F'd............. Equation 1
Where:
- K.E = Kinetic energy of the train
- F' = Friction force provided by the brakes
- d = distance
Make F' the subject of the equation
- F' = K.E/d............ Equation 2
From the question,
Given:
Substitute these values into equation 2
- F' = (8.1 ×10⁶)/270
- F' = 30000 N
Hence, the friction force provided by the brakes is 30000 N
Learn more about friction force here: brainly.com/question/13680415
The distance covered is 25.9 m.
<h3>How deep is the cave?</h3>
We know that the speed of sound refers to the speed with which an sound moves in an object.
Given that;
speed of sound = 345m/s
Time taken = 0.15s
We know that;
v = 2d/t
v = speed of sound
d = distance
t = time taken
vt = 2d
d = vt/2
d = 345m/s * 0.15s/2
d = 25.9 m
Learn more about speed of sound:brainly.com/question/15137350
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No. The correct answer is A.