Answer:
h f = Wf + K
where the total energy available is h f, Wf is the work function or the work needed to remove the electron and K is the kinetic energy of the removed electron
If K = zero then hf = Wf
Wf = h f = h c / λ or
λ = h c / Wf = 6.63E-34 * 3.0E8 / (3.7 * 1.6E-19)
λ = 6.63 * 3 / (3.7 * 1.6) E-7 = 3.36E-7
This would be 3360 angstroms or 336 millimicrons
Visible light = 400-700 millimicrons
Answer:
The earth's gravitational force on the sun is equal to the sun's gravitational force on the earth
Explanation:
Newton's third law (law of action-reaction) states that:
"When an object A exerts a force (called action) on an object B, then object B exerts an equal and opposite force (called reaction) on object A"
In other words, when two objects exert a force on each other, then the magnitude of the two forces is the same (while the directions are opposite).
In this problem, we can call the Sun as "object A" and the Earth as "object B". According to Newton's third law, therefore, we can say that the gravitational force that the Earth exerts on the Sun is equal (in magnitude, and opposite in direction) to the gravitational force that the Sun exerts on the Earth.
Either no forces or a balanced group of forces
(not a group of "balanced forces"; there's no such thing)
Answer:
Friction is a force that holds back the movement of a sliding object.
Explanation:
The two types of friction: Static friction and Kinetic friction. Static friction operates between two surfaces that aren't moving relative to each other, while kinetic friction acts between objects in motion.
The initial velocity of Ms. Stafford is
, while her acceleration is
This is a uniform accelerated motion, so we can calculate the total distance travelled by Ms. Stafford in a time of
using the law of motion for a uniform accelerated motion:
