Acar moves in a straight line at 22.0 m/s for 10.0miles, then at 30.0 m/s for another 10.0miles. calculate the car’s average speed in m/s

25.38 m/s

Explanation:

We have a straight line where the car travels a total distance , which is divided into two segments :

(1)

Where

On the other hand, we know speed is defined as:

(2)

Where is the time, which can be isolated from (2):

(3)

Now, for the first segment the car has a speed , using equation (3):

(4)

(5)

(6) This is the time it takes to travel the first segment

For the second segment the car has a speed ,  hence:

(7)

(8)

(9) This is the time it takes to travel the secons segment

Having these values we can calculate the car's average speed :

(10)

(11)

Finally:

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards