What is the difference between mechanical waves and electromagnetic waves?

A wire has a current that flows to the right.

Natalija [7]

D) circles around the wire that go in at the bottom

4 0

2 years ago

A frog falls from its rainforest tree. If we ignore wind resistance, (a) how much time does it take the frog to fall a distance

gtnhenbr [62]

Answer:

Explanation:

a) Using the equation of motion

S = ut + 1/2gt²

S is the distance of fall

g is the acceleration due to gravity

t is the time taken

Given S = 12.0m, g = 9.81m/s^2, un= 0m/s

12 = 0+1/2(9.81)t²

12 = 4.905t²²²

t² = 12/4.905

t² = 2.446

t = √2.446

t = 1.56secs

b) To determine how fast is the frog falling at this point, we need to calculate the speed of the frog. Using the equaton v = u+gt

v = 0+9.81(1.56)

v = 15.34m/s

Hence the frog is falling at the rate of 15.34m/s

5 0

2 years ago

A skydiver falls out of a plane from rest, and experiences no air resistance. Eventually, this skydiver reaches a velocity of 33

shusha [124]

Answer:

the time taken for the motion is 3.37 s

Explanation:

Given;

initial velocity of the skydiver, u = 0

final velocity of the skydiver, v = 33 m/s

The time taken for the motion is calculated as;

v = u + gt

33 = 0 + 9.8t

33 = 9.8t

t = 33 / 9.8

t = 3.37 s

Therefore, the time taken for the motion is 3.37 s

3 0

2 years ago

[1] The assembly starts from rest and reaches an angular speed of 150 rev/min under the action of a 20-N force T applied to the

ExtremeBDS [4]

Answer:

t = 5.89 s

Explanation:

To calculate the time, we need the radius of the pulley and the radius of the sphere which was not given in the question.

Let us assume that the radius of the pulley ( $r_p$ ) = 0.4 m

Let the radius of the sphere (r) = 0.5 m

w = angular speed = 150 rev/min = (150 × 2π / 60) rad/s = 15.708 rad/s

Tension (T) = 20 N

mass (m) = 3 kg each

$\int\limits^0_t {Tr_p} \, dt=H_2-H_1\\( Tr_p)t=4rm(rw)\\( Tr_p)t=4r^2mw$

$t = \frac{4r^2mw}{Tr_P}$

Substituting values:

$t = \frac{4r^2mw}{Tr_P}= \frac{4*(0.5)^2*3*15.708}{20*0.4}=5.89s$

7 0

2 years ago

Read 2 more answers

A small sphere is hung by a string from the ceiling of a van. When the van is stationary, the sphere hangs vertically. However,

Paraphin [41]

Answer: 42.49 $m/s^{2}$

Explanation:

To solve this, we need to keep in mind the following:

While the sphere hangs it is under the effect of gravity. It is creating a Angle of 90° taking the roof as a reference.

Gravity can be noted as a Acceleration Vector. The magnitud for Earth's Gravity is a constant: 9.81 $m/s^{2}$

The acceleration of the Van will affect the sphere also, but this accelaration will be on the X-axis and perpendicular to the gravity. Because this two vectors are taking action under the sphere they will create a angle. This angle can be measured as a relation of the two magnitudes.

Tangent (∅) = Opossite Side / Adyacent Side

By trigonometry, we know the previous formula. This formula allows us to find the Tangent of a angle as a relation between the two perpendiculars magnitudes. In this case the Opossite Side will be the Gravity Accelaration, while the Adyancent Side is the Van's Acceleration.

(1) Tangent (∅) = Gravity's Acceleration (G) / Van's Acceleration (Va)

Searching for the Va in (1)

Va = G/Tan(∅)

Where ∅ in this case is equal to 13.0°

Va = 9.81 $m/s^{2}$ / Tan(13.0°)

Va = 42.49 $m/s^{2}$

The vans acceleration need to be 42.49 $m/s^{2}$ to create an angle of 13° with the Van's Roof

3 0

3 years ago