Assuming it starts at rest, the roller coaster only has potential energy at the top of the hill, which is
When it reaches the bottom, its potential energy will have converted to kinetic energy,
where is its velocity at that point. By the law of conservation of energy, assuming no loss of energy due to other sources (e.g. sound, heat), we have
Answer:
The range of the projectile is 66.7 meters.
Explanation:
The range of a projectile is given by the following expression as :
..............(1)
The range can be calculated using equation (1). Putting the values of all parameters we get :
R = 66.7 meters
So, the range of the projectile is 66.7 meters. Hence, this is the required solution.
Answer:
piece of submerged iron
Explanation:
The buoyant force is given by:
where
is the density of the liquid (in this case, water)
is the submerged part of the object
g is the acceleration due to gravity
In this problem, the liquid used in the two examples is the same, water, so is the same; and g is the same as well. Therefore, the only difference between the two examples is
.
For the piece of wood, we are told that the object is floating, so only a fraction of its total volume of 25.0 cm3 will be submerged: therefore the submerged volume will be less than 25.0 cm3. On the contrary, the problem tells us that the piece of iron is submerged, so the submerged volume in this case is 25.0 cm3. Therefore, the submerged volume for the iron is greater than for the piece of wood, so the buoyant force of the piece of iron is greater.