If the ladder is vertical, then the work done in ascending equals his increase in potential energy.
For a man of mass (m) climbing height (h), the PE is (mgh), where g is the acceleration due to gravity.
If he does this in time t, his average power (rate of working) is:
mgh / t
= 80 * 9.81 * 6 / 12
= 392.4 W.
If the ladder is not vertical but inclined at an angle the horizontal, the power is mgh sin(a) / t.
Answer:
yes
Explanation:
By definition, the speed of an object is the rate of change of its position.Velocity, on the other hand, is the measurement of the rate and direction of change in the position of an object. Since it is a vector physical quantity, both magnitude and direction are required to define it
Answer:
λ = 864 nm
Explanation:
To find the wavelength of the light you use the following formula, which determines the position of the m-th fringe in an interference pattern:
(1)
ym: position of a bright fringe
D: distance from the slits to the screen = 3,7 m
d: distance between slits = 0,2mm = 0,2 *10^-3 m
m: order of the fringe
λ: wavelength of the light
You have the distance from the central peak to the third fringe (0,048m). Then, you can use the equation (1) with m=3 and solve for the wavelength:
henc, the wavelength of the light is 864nm
The angular momentum calculated with respect to the axis of rotation of an object is given by:
where m is the object's mass, v is its tangential speed, and r is its distance from the axis of rotation.
In case of a man on a Ferris wheel, we need to have these quantities in order to calculate his angular momentum. These quantities corresponds to:
- m, the mass of the man
- v, the tangential speed of the wheel at its edge
- r, the radius of the wheel
It is possible to calculate the angular momentum even if we don't know v, the tangential speed. In this case, we need to know at least the angular velocity
(because from this relationship we can find the tangential speed:
) or the period of rotation of the wheel, T (because we can find the angular velocity from it:
).