PE stands for Potential Energy. It is the stored energy in an object due to its position with respect to some reference. It is expressed in Joules.
P.E = m * g * h OR P.E. = mgh
m - mass of the body
g - acceleration due to gravity
h - height attained due to the body's displacement.
K.E. stands for Kinetic Energy. It is the energy possessed by a body due to its motion.
K.E = 1/2 mv² where m = mass of the body; v = velocity with which the body is moving.
Answer:
Yes . Frictions was not included for the calculation for acceleration .
Explanation:
This is because we're considering the weight of an object which isn't acceleration i:e frictionless.
If friction is included, the equation for acceleration becomes.
F= ma,(Newton second law of motion)
where F=frictional force , m =mass of the object and a=acceleration..
So therefore, a = F/m.
Answer:
Mechanical weathering is the physical breakdown of rock into smaller pieces. Chemical weathering is the breakdown of rock by chemical processes.
Explanation:
Mechanical weathering (also called physical weathering) breaks rock into smaller pieces. These smaller pieces are just like the bigger rock, just smaller. That means the rock has changed physically without changing its composition. The smaller pieces have the same minerals, in just the same proportions as the original rock.
Chemical weathering is the other important type of weathering. Chemical weathering is different from mechanical weathering because the rock changes, not just in size of pieces, but in composition Chemical weathering works through chemical reactions that cause changes in the minerals.
Answer:
Explanation:
Let us calculate the average velocity .
Average velocity = total distance / total time
Time taken to drive first 15 mi
= 15 / 60 = .25 h
Time taken to drive next 15 mi
= 15 / 30 = .5 h
Total time = .25 + .5 = .75 h
Total distance = 30 mi
average speed = 30 / .75
= 40 mi / h
So average speed is 40 mph which is less than given velocity of 45 mph .
Hence if she travels at 45 mph , she will take less time .
