I assume the 100 N force is a pulling force directed up the incline.
The net forces on the block acting parallel and perpendicular to the incline are
∑ F[para] = 100 N - F[friction] = 0
∑ F[perp] = F[normal] - mg cos(30°) = 0
The friction in this case is the maximum static friction - the block is held at rest by static friction, and a minimum 100 N force is required to get the block to start sliding up the incline.
Then
F[friction] = 100 N
F[normal] = mg cos(30°) = (10 kg) (9.8 m/s²) cos(30°) ≈ 84.9 N
If µ is the coefficient of static friction, then
F[friction] = µ F[normal]
⇒ µ = (100 N) / (84.9 N) ≈ 1.2
Answer:
0.43 s
Explanation:
We have the following parameters:
Initial velocity, u = 7.4 m/s
Acceleration of gravity, g = 9.8 
Distance, s = 43 in + 10 ft = 1.092 m + 3.048 m = 4.14 m
Time, t = ?
Using the equation of motion 
, we have
Using the quadratic formula 
where a = 4.9, b = 7.4 and c = - 4.14, and solving for the positive value of t only, we have
s
Answer:
a) v = 2,9992 10⁸ m / s
, b) Eo = 375 V / m
, B = 1.25 10⁻⁶ T,
c) λ = 3,157 10⁻⁷ m, f = 9.50 10¹⁴ Hz
, T = 1.05 10⁻¹⁵ s
, UV
Explanation:
In this problem they give us the equation of the traveling wave
E = 375 cos [1.99 10⁷ x + 5.97 10¹⁵ t]
a) what the wave velocity
all waves must meet
v = λ f
In this case, because of an electromagnetic wave, the speed must be the speed of light.
k = 2π / λ
λ = 2π / k
λ = 2π / 1.99 10⁷
λ = 3,157 10⁻⁷ m
w = 2π f
f = w / 2 π
f = 5.97 10¹⁵ / 2π
f = 9.50 10¹⁴ Hz
the wave speed is
v = 3,157 10⁻⁷ 9.50 10¹⁴
v = 2,9992 10⁸ m / s
b) The electric field is
Eo = 375 V / m
to find the magnetic field we use
E / B = c
B = E / c
B = 375 / 2,9992 10⁸
B = 1.25 10⁻⁶ T
c) The period is
T = 1 / f
T = 1 / 9.50 10¹⁴
T = 1.05 10⁻¹⁵ s
the wavelength value is
λ = 3,157 10-7 m (109 nm / 1m) = 315.7 nm
this wavelength corresponds to the ultraviolet
<h3><u>Answer</u>;</h3>
-The total momentum of an isolated system is constant.
-The total momentum of any number of particles is equal to the vector sum of the momenta of the individual particles.
-The vector sum of forces acting on a particle equals the rate of change of momentum of the particle with respect to time.
<h3><u>Explanation</u>;</h3>
- Momentum is a vector quantity, and therefore we need to use vector addition when summing together the momenta of the multiple bodies which make up a system.
- The vector sum of forces acting on a particle is equivalent to the rate of change of momentum of the particle with respect to time. This is according to the Newton's second Law of motion. In mathematical terms, ֿF = d ֿp/dt, that is F= ma.
- According to the Law of conservation of Momentum, or a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision.
Beats are interference patterns between two tones of different frequencies. To prove the skeptic first, play the recorded audio as there are no beats in it. Now take two sound sources with different frequencies. When both sources are turned on, we hear notes that rise and fall at equal intervals. That's what's called beats.
A frequency beat occurs when two waves with different frequencies overlap, causing alternating cycles of constructive and destructive interference between the waves.
When we tap the table with our finger, then put our ear to the table, and tap the table surface as far as 30 cm from our ear. Then the sound of beats on the table will sound louder when we put our ears on the table. So, it can be concluded that solid objects can conduct sound better than air. This is because the molecules or particles of solid objects are denser than air.
Learn more about the beat's frequency at brainly.com/question/14157895
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