Explanation :
It is given that the ad says the ride is 50 meters tall and reaches a speed of 28m/sec at the bottom.
The efficiency is defined as the ratio of the output energy and the input energy.
In this case, the output energy is kinetic energy and the input is potential energy.
Output energy,
Input energy,
Efficiency becomes :
or
The ride is 80% efficient.
Answer:
C
Explanation:
Alveoli are tiny functioning structures that compose your lungs. They help with respiration. They have a large total surface area, which is very useful for respiration. The more surface area there is, the more transactions can happen. Which means that breathing will be easier/faster when you have more alveoli. (Please rate this answer if you have time!)
Answer:
500 Ns
Explanation:
According to the impulse theorem, the change in momentum of an object is equal to the impulse exerted on it. Mathematically:
where
is the change in momentum of the object
I is the impulse exerted, which is the product of
F, the net force exerted
, the time interval during which the force is applied
In this problem,
F = 100 N is the force applied on the wagon
is the time interval
Substituting, we find the change in momentum of the wagon:
Answer:
25J
Explanation:
Given parameters:
Mass of the dog = 10kg
Speed of the dog = 5m/s
Unknown:
The minimum energy required to stop the dog = ?
Solution:
The dog is moving with a kinetic energy and to stop the dog, an equal amount of kinetic energy generated must be applied to the dog.
To find the kinetic energy;
K.E = m v²
m is the mass
v is the velocity
Now insert the parameters and solve;
K.E = x 10 x 5 = 25J
Answer:
distance difference would a) increase
speed difference would f) stay the same
Explanation:
Let t be the time the 2nd skydiver takes to travel, since the first skydiver jumped first, his time would be t + Δt where Δt represent the duration between the the first skydiver and the 2nd one. Remember that as t progress (increases), Δt remain constant.
Their equations of motion for distance and velocities are
Their difference in distance are therefore:
(As
So as time progress t increases, Δs would also increases, their distance becomes wider with time.
Similarly for their velocity difference
Since g and Δt both are constant, Δv would also remain constant, their difference in velocity remain the same.
This of this in this way: only the DIFFERENCE in speed stay the same, their own individual speed increases at same rate (due to same acceleration g). But the first skydiver is already at a faster speed (because he jumped first) when the 2nd one jumps. The 1st one would travel more distance compare to the 2nd one in a unit of time.