First the velocity drops to zero in 1.2 secs. In those seconds it went upwards for 7.2 m, then it went from 87.2 to 0m. x-x0=v0*t+1/2*g*t^2 ergo t=sqrt(2x/g) that is 4.1761 s. Finally the total time required is 5.3761 s
As we sit in a chair, Action force will be only in one direction and that direction would be downward only.
In short, Your Answer would be Option A
Hope this helps!
Answer;
Amount of time the two substances are in contact
Area in contact between the two substances
Specific heat of the material that makes up the substances
Explanation;
The change in temperature of a substance is caused by heat energy. The change in temperature will depend on factors such as mass of the substance, the type of material it is made from, the time taken , specific heat of the material that makes the substance, and also the area of contact.
The amount of time the two substances are in contact affect the change in temperature such that if the two bodies are in contact for a longer time then a bigger change in temperature will be observed.
Specific heat capacity also determines the change in temperature that will be observed, such that a substance with a bigger specific heat capacity will record a small change in temperature.
From rest, a rock is dropped from a garage roof. The roof is 6.0 meters above ground level. The rock will reach the earth at a speed of 10.849 meters per second.
<h3>What is velocity?</h3>
The change of displacement with respect to time is defined as the velocity. Velocity is a vector quantity.
it is a time-based component. Velocity at any angle is resolved to get its component of x and y-direction.
Given data:
V(Final velocity)=? (m/sec)
h(height)= 6.0 m
u(Initial velocity)=0 m/sec
g(gravitational acceleration)=9.81 m/s²
Newton's third equation of motion:

Hence, the velocity of the rock as it hits the ground will be 10.849 m/sec.
To learn more about the velocity refer to the link ;
brainly.com/question/862972
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