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3 years ago

A radar operates at a wavelength of 3 centimeters. what is the frequency of the these waves? the speed of light is 3 × 108 m/s .

1 answer:

4 0

We are given information:
λ $= wavelength = 3cm = 0.03m \\ 
c = speed of light = 3* 10^{8}m/s$

Formula that connects wavelength and frequency is:
$frequency= \frac{speed of light}{wavelength} \\ f= \frac{3* 10^{8}}{0.03} \\ f=1 * 10^{10} Hz = 10GHz$

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What is the physical representation of the area under a force versus extension or compression curve?

lidiya [134]

The compression curve would be theoretically given for a system of bodies in which the spring applies the force (Although in the same way the following process can be extrapolated to any system, depending on the type of Force to consider) For a spring mass system, the strength is given by Hooke's law as

$F = Kx$

Where,

K = Spring constant

x = Displacement

If we integrate based on distance we would have

$\int F = \int K x dx$

This integral represents the area under the Force Curve based on each distance segment traveled.

$\int F = K \int xdx$

$\int F = K (\frac{1}{2} x^2)$

$\int F = \frac{1}{2} Kx^2$

This is the same formula that represents the elastic potential energy of a body. Therefore the correct answer is D.

5 0

3 years ago

If frequency is kept constant, how are the velocity and wavelength of a wave related?

Elan Coil [88]

<h3>Answer;</h3>

Velocity and wavelength are directly proportional when frequency is kept constant.

<h3>Explanation;</h3>

Frequency of a wave is the number of complete oscillations made by a given wave in one second.
Wavelength on the other hand, is the distance between two successful crests or troughs in a transverse wave or two successful rarefactions or compressions in a longitudinal waves.
The speed of a wave is given by the product of the frequency of a wave and the wavelength.
Speed = Frequency × wavelength, 
Therefore, if frequency is kept constant, then the speed of a wave is directly proportional to the wavelength, such that an increase in wavelength increases the speed of the wave and vice versa.

3 0

3 years ago

Read 2 more answers

A 3.8kw elective motor powers an inclined conveyer belt. It is designed to lift heavy boxes from the warehouse floor to loading

zhannawk [14.2K]

Answer:

See the answers below

Explanation:

To solve this problem we must use the definition of power and work in physics.

The function of the conveyor belt is to carry the boxes from an initial point that is at low altitude to an end point that is at high altitude. In this way the conveyor belt prints a speed to the box to be able to raise it to the required vertical distance.

Since we have a velocity at the beginning and then we place the box at a high position, where then the box remains at rest, we can say that it converts kinetic energy to potential energy.

Power is defined as the relationship of work over time. Therefore we have:

$P=W/t$

where:

P = power = 3.8 [kW] = 3800 [W]

W = work [J]

t = time = 14 [s]

$W=P*t\\W=3800*14\\W= 53200[J] = 53.2[kJ]$

Since the given time is equal to the given time at Point b, we can use the same work calculated.

We know that work is defined as the product of force by the distance traveled.

$W =F*d$

So, the force is equal to:

$F=W/d\\F=53200/5.3\\F=10037.73[N]$

Now we know that force is defined as the product of mass by gravitation acceleration.

$F =m*g$

where:

F = force or weight = 10037.73 [N]

g = gravity acceleration = 9.81 [m/s²]

m = mass [kg]

$m=F/g\\m = 10037.73/9.81\\m = 1023.2 [kg]$

This part can be solved by means of the energy conservation theorem, where the potential energy is transformed into kinetic energy or vice versa.

$E_{pot}=m*g*h = E_{kin}=0.5*m*v^{2}$

where:

h = elevation = 4.7 [m]

v = velocity [m/s]

$m*g*h=0.5*m*v^{2}\\g*h=0.5*v^{2} \\v=\sqrt{\frac{g*h}{0.5} } \\v=\sqrt{\frac{9.81*4.7}{0.5} } \\v = 9.6 [m/s]$

7 0

3 years ago

on a very muddy football field, a 120 kg linebacker tackles an 75 kg halfback. immediately before the collision, the linebacker

DIA [1.3K]

Momentum
- a vector quantity; has both magnitude and direction
- has the same direction as object's velocity
- can be represented by components x & y.

Find linebacker momentum given m₁ = 120kg, v₁ = 8.6 m/s north
P₁ = m₁v₁
P₁ = (120)(8.6)
[ P₁ = 1032 kg·m/s ] = y-component, linebacker momentum

Find halfback momentum given m₂ = 75kg, v₂ = 7.4 m/s east
P₂ = m₂v₂
P₂ = (75)(7.4)
[ P₂ = 555 kg·m/s ] = x-component, halfback momentum

Find total momentum using x and y components.
P = √(P₁)² + (P₂)²
P = √(1032)² + (555)²
[[ P = 1171.77 kg·m/s ]] = magnitude

!! Finally, to find the magnitude of velocity, take the divide magnitude of momentum by the total mass of the players.
P = mv
P = (m₁ + m₂)v
1171.77 = (120 + 75)v [solve for v]
v = 1171.77/195
v = 6.0091 ≈ 6.0 m/s

If asked to find direction, take inverse tan of x and y components.
tanθ = (y/x)
θ = tan⁻¹(1032/555)
[ θ = 61.73° north of east. ]

The magnitude of the velocity at which the two players move together immediately after the collision is approximately 6.0 m/s.

6 0

3 years ago

2.1 Define Resultant vector

lord [1]

Explanation:

In vector geometry, the resultant vector is defined as: “A resultant vector is a combination or, in simpler words, can be defined as the sum of two or more vectors which has its own magnitude and direction.”

I hope it's helpful!

3 0

3 years ago