A fullback is running down the football field in a straight line. He starts at the 0-yard line at 0 seconds. At 1 second, he is on the 10-yard line; at 2 seconds, he is at the 20-yard line; at 3 seconds, he is at the 30-yard line; and at 4 seconds, he is at the 40-yard line. This is evidence that a.) he is accelerating

b.) he is moving with a constant speed (on average)

c.) he is covering a greater distance in each consecutive second

Option (b) he is moving with a constant speed (on average)

Explanation:

To know which option is correct, let us calculate the speed at each time.

Case 1:

Distance = 10 yard

Time = 1 s

Speed =?

Speed = distance / time

Speed = 10 / 1

Speed = 10 yard/s

Case 2:

Distance = 20 yard

Time = 2 s

Speed =?

Speed = distance / time

Speed = 20 / 2

Speed = 10 yard/s

Case 3:

Distance = 30 yard

Time = 3 s

Speed =?

Speed = distance / time

Speed = 30 / 3

Speed = 10 yard/s

Case 4:

Distance = 40 yard

Time = 4 s

Speed =?

Speed = distance / time

Speed = 40 / 4

Speed = 10 yard/s

From the calculations made above, we can see clearly that the speed at each case is the same i.e constant. This is true because he is covering the same distance with respect to time.

This also means that the footballer is not accelerating as his speed remains the same i.e constant.

Thus, option B gives the correct answer to the question.

you get 2.3=1.21*\frac{a}2 or 4.6=1.21a or a=3.802 (b)

explanation: