Answer:
i wanna say 11 forgive me if wrong.
Explanation:
Explanation:
They probably put "rolls without slipping" in there to indicate that there is no loss in friction; or that the friction is constant throughout the movement of the disk. So it's more of a contingency part of the explanation of the problem.
(Remember how earlier on in Physics lessons, we see "ignore friction" written into problems; it just removes the "What about [ ]?" question for anyone who might ask.)
In this case, you can't ignore friction because the disk wouldn't roll without it.
As far as friction producing a torque... I would say that friction is a result of the torque in this case. And because the point of contact is, presumably, the ground, the friction is tangential to the disk. Meaning the friction is linear and has no angular component.
(You could probably argue that by Newton's 3rd Law there should be some opposing torque, but I think that's outside of the scope of this problem.)
Hopefully this helps clear up the misunderstanding for you.
Answer:
a) W = 3.87 10⁻⁴ J
, b) P = 3.10 10⁻³ Pa
, c) λ = 671. 6 nm
, d) frequency does not change
, e) Emax = 1.39 C / m and f) Bmax = 4.7 10⁻⁹ T
Explanation:
a) Let's use the concepts of power that is work for the unit of time and work is the change of kinetic energy
P = W / t
An electromagnetic wave has an intensity
I = P / A =
W = P t
W = 258 10⁻³ 1.5 10⁻³
W = 3.87 10⁻⁴ W s
W = 3.87 10⁻⁴ J
b) the radiation pressure is given by the ratio
P = I / c
Where I is the intensity
I = Powers / A
A = π r² = π (d/2)²
I = 258 10⁻³ / π (297.5 10⁻⁶)²
I = 9.29 10 5 W / m²
P = 9.29 10⁵/3 10⁸
P = 3.10 10⁻³ Pa
c) The wavelength when passing a measured of different refractive index changes in the way
λ = λ₀ / n
λ = 900 10⁻⁹ / 1.34
λ = 671.6 10⁻⁹ m
λ = 671. 6 nm
d) when the light strikes a medium creates a forced oscillation in the electrons of the medium, this is a resonance phenomenon, so the frequency does not change
e) The maximum electric field is
I = Emax2 / 2 μ₀ c
Emax = Ra (2 μ₀ c I)
Emax = Ra (2 4 π 10⁻⁷ 3 10⁸ 258 10⁻³)
Emax = 1.39 C / m
f) the elective and magnetic fields are related
c = Emax Bmax
Bmax = Emax / c
Bmax = 1.39 / 3 10⁸
Bmax = 4.7 10⁻⁹ T
Answer:
i d k about that but I know it`s a Polish thing
Answer: Force applied by trampoline = 778.5 N
<em>Note: The question is incomplete.</em>
<em>The complete question is : What force does a trampoline have to apply to a 45.0 kg gymnast to accelerate her straight up at 7.50 m/s^2? note that the answer is independent of the velocity of the gymnast. She can be moving either up or down or be stationary.
</em>
Explanation:
The total required the trampoline by the trampoline = net force accelerating the gymnast upwards + force of gravity on her.
= (m * a) + (m * g)
= m ( a + g)
= 45 kg ( 7.50 * 9.80) m/s²
Force applied by trampoline = 778.5 N
