We can calculate the length of each spring by using the relationship:

where
F is the force applied to the spring
k is the spring constant
x is the length of the spring (measured with respect to its rest position)
Re-arranging the equation, we have

The force applied to both spring is F=60 N. Spring A has spring constant of k=4 N/m, therefore its length with respect to its rest position is

Spring B has spring constant of k=5 N/m, so its length with respect to its rest position is

Therefore, the correct answer is
<span>
D.Spring A is 3 m longer than spring B because 15 – 12 = 3.</span>
Answer:
Running or Jogging
Running and jogging are both great options for aerobic conditioning. Whether you run at the gym or outside, you are in control of setting the intensity of your workout. When aiming to build muscle mass, you can add more resistance or jog at an incline, along with increasing your speed.
Explanation:
By molecules of different substances :) <span />
(a)
mass of the car: m=950 kg
Initial speed: 
Final speed:
(the car comes to rest)
distance: 
We can find the acceleration by using the following SUVAT equation:

Re-arranging it and replacing the numbers, we find the acceleration

So now we can calculate the force using Newton's second law:

And the negative sign means the force is applied against the direction of motion.
(b)
In this case, the distance is different:

so, the acceleration in this case is

And so, the force applied in this case is

which is much larger than the force exerted in the previous exercise.