When an object is free-falling, no other force is acting upon it but the gravitational force. Because of this, the equations of motion are simplified. We can determine first the initial velocity:
v = √2gy = √2(9.81)(4.9) = 9.805 m/s
Then, we use this to the equation below:
y = vt + 1/2*at²
y = (9.805)(0.5) + 1/2(9.81)(0.5)²
y = 6.13 m
Hey, can you state your question a little more clearly
Answer:
(d) 9 × 10^{3] J
Explanation:
from the question we are given the following:
weight of the man = 6.0 × 10 ^ {2} N
average speed (v) = 3 m/s
time (t) = 3 s
potential energy (U) = ?
We can calculate the increase in potential energy of the man by applying the formula below
increase in potential energy = P₂ - P₁
where
- P₁ is the initial potential energy
- P₂ is the final potential energy
- Potential energy = mass x acceleration due to gravity x height
From physic we know that weight = mass x acceleration due to gravity
- We should take note that the distance in this case is also our height, and we can get it from the formula distance = velocity x time
- Distance = 3 x 5 = 15 meters
- Initial potential energy P₁ is zero because the person was initially in motion and potential energy is the energy at rest.
therefore
potential energy = 6.0 × 10 ^ {2} × 15 = 9 × 10^{3] J
Answer:
0.657 seconds
Explanation:
speed of wave= wavelength / time period
so
time period= wavelength / speed
= 4.6/7
=0.657 sec
Answer:
The basic principle on which the electric iron works is that when a current is passed through a piece of wire, the wire heats up. This heat is distributed to the sole (base) plate of the electric iron through conduction.