A10 kg rock is suspended 320 m above the ground. calculate the approximate speed with which the rock hits the ground. v = a. 6300 m/s b. 79 m/s c. 56 m/s d. 40. m/s

B. 79 m/s

Explanation:

Since we have information about the distance of the fall, we can use the following formula to find the final velocity of the object:

clearing for

where is the final velocity (when it hits the ground), the initial velocity, is the acceleration of gravity (), and is the height from where the rock is dropped, in this case:

Assuming that the rock was only dropped without adding an initial velocity, is zero.

Substituting all the values in the formula:

The value that best approximates from the options is 79 m/s,  the answer is B.

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)