d = distance traveled by her on her bicycle on a long flat road = 24 kilometer
t = time taken by her to travel distance "d" on her bicycle on a long flat road = 1.2 hours
v = average speed of vivian = ?
we know that average speed is given as
v = d/t
inserting the values in the above formula
v = 24 kilometer / 1.2 hour
v = 20 kilometer/hour
hence the correct choice is
C) 20 km/h
Valleys, waterfalls, flood plains, meanders, and oxbow lakes
Answer:
the velocity is zero, the acceleration is directed downward, and the force of gravity acting on the ball is directed downward
Explanation:
Is this exercise in kinematics
v = v₀ - g t
where g is the acceleration of the ball, which is created by the attraction of the ball to the Earth.
At the highest point
velocity must be zero.
The acceleration depends on the Earth therefore it is constant at this point and with a downward direction.
The force of the earth on the ball is towards the center of the Earth, that is, down
all other alternatives are wrong
Gravitational potential energy can be calculated using the formula <span>PE = m × g × h, where g is the gravitational acceleration and is constant hence the energy is dependent directly to mass and the height of the object. Hence more PE is registered when the object is heavier and/or at greater initial height. </span>
Mechanics is dealing with forces that are effecting some body, electrostatics is about electrical fields of not moving bodies, and quantum mechanics is dealing with quantum states of atoms.
Thermodynamics as the word say, is dealing with thermal energy that is moving (transferring from one body to another or even better from one medium to another).
Answer is C <span />