Answer:
a) the elastic force of the pole directed upwards and the force of gravity with dissects downwards
Explanation:
The forces on the athlete are
a) at this moment the athlete presses the garrolla against the floor, therefore it acquires a lot of elastic energy, which is absorbed by the athlete to rise and gain potential energy,
therefore the forces are the elastic force of the pole directed upwards and the force of gravity with dissects downwards
b) when it falls, in this case the only force to act is batrachium by the planet, this is a projectile movement for very high angles
c) When it reaches the floor, it receives an impulse that opposes the movement created by the mat. The attractive force is the attraction of gravity.
Answer:
λ = 2.7608 x 10⁻⁷ m = 276.08 nm
Explanation:
The work function of a metallic surface is the minimum amount of photon energy required to release the photo-electrons from the surface of metal. The work function is given by the following formula:
Work Function = hc/λ
where,
Work Function = (4.5 eV)(1.6 x 10⁻¹⁹ J/1 eV) = 7.2 x 10⁻¹⁹ J
h = Plank's Constant = 6.626 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = longest wavelength capable of releasing electron.
Therefore,
7.2 x 10⁻¹⁹ J = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/λ
λ = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(7.2 x 10⁻¹⁹ J)
<u>λ = 2.7608 x 10⁻⁷ m = 276.08 nm</u>
Answer:
It will take you 30.8 s to travel the 120 m of the ramp.
Explanation:
Hi there!
The equation for the position of an object moving in a straight line is:
x = x0 + v * t
Where:
x = position at time t
x0 = initial position
v = velocity
t = time
In this case, we will consider the start of the ramp as the origin of our reference system so that x0 = 0.
Now, let´s calculate the speed of the person walking on the ground:
x = v * t
120 m = v * 72 s
v = 120 m / 72 s
v = 1.7 m/s
If you walk on the ramp with that speed, your total speed will be your walking speed plus the speed of the ramp because both are in the same direction. Then, using the equation for the position:
x = v * t
In this case, v = speed of the ramp + walking speed
v = 2.2 m/s + 1.7 m/s = 3.9 m/s
120 m = 3.9 m/s * t
t = 120 m / 3.9 m/s = 30.8 s
It will take you 30.8 s to travel the 120 m
