Determine the acceleration (in m/s2) of an object which . 1. moves in a straight line with a constant speed of 20.0 m/s for 12.0 seconds 2. changes its velocity from 12.1 m/s to 23.5 m/s in 7.81 seconds 3. changes its velocity from 0.0 mi/hr to 60.0 mi/hr in 4.20 seconds 4. accelerates from 33.4 m/s to 18.9 m/s over a distance of 109 m

1) 0 m/s²

2) 1.5 m/s²

3) 6.38 m/s²

4) -3.47 m/s²

Explanation:

The acceleration is given by:

1)

For the first question, the acceleration is zero, because there is no change on its velocity:

2)

3) here we have to make an conversion:

4) here we have to use the following formula:

the total distance traveled by the car is

30km + 49km = 79 km .

grav force prop 1/r squared 2r all squared is 4rsquared 1/4rsquared quartered