Me pls which which of the following graphs correctly shows the relationship between ke and velocity? *

Option 3.

Explanation:

Formula for kinetic energy is

K.E = (1 / 2) * (m * v ^ 2)

Assuming mass to be constant,

We can see that K.E is proportional to v^2.

It means that when you substitute the value of velocity in v, kinetic energy increases with v^2.

Option 1 and 2 are eliminated because the relationship between kinetic energy and velocity in the graph is shown as linear. We already know from formula that the relationship is not linear.

Option 4 is incorrect because kinetic energy must be zero when velocity is zero. This graph shows kinetic energy is becoming infinite as velocity tends to 0.

So option 3 is correct answer.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s