If a wheel rotates 5 times in 90 seconds, what is the period and frequency

The Sun appears at an angle of 48.4° above the horizontal as viewed by a dolphin swimming underwater. What angle does the sunlig

Luden [163]

Answer:

4.57 degree

Explanation:

As the dolphin is under water, so the angle is angle of refraction which is equal to 48.4 degree.

refractive index of water, n = 1.333

Let the angle of incidence which is the angle between the incident ray and the normal is i.

By use of Snell's law

$n = \frac{Sin i}{Sin r}$

$1.333 = \frac{Sin i}{Sin 48.4}$

$Sin i = 1.333\times Sin 48.4 = 0.9968$

i = 85.43 degree

Angle made with the horizon = 90 - 85.43 = 4.57 degree

6 0

3 years ago

A 1.15-kg mass oscillates according to the equation where x is in meters and in seconds. Determine (a) the amplitude, (b) the fr

ANEK [815]

The complete question is;

A 1.15-kg mass oscillates according to the equation x = 0.650 cos(8.40t) where x is in meters and t in seconds. Determine (a) the amplitude, (b) the frequency, (c) the total energy, and (d) the kinetic energy and potential energy when x = 0.360 m.

Answer:

A) Amplitude; A = 0.650 m

B) Frequency; f = 1.337 Hz

C) total energy = 17.142 J

D) Kinetic energy = 11.884 J

Potential Energy = 5.258 J

Explanation:

We are given;

Mass;m = 1.15 kg

Equation; x = 0.650 cos (8.40t)

(a) The standard form of a wave function is in the form y(x,t) = Asin(kx−ωt+ϕ)

So, comparing terms in our equation in the question to this, the amplitude is;

A = 0.650 m

(b) we know that formula for frequency is;

f = ω/2π

Again, comparing terms in the standard equation and our question, we can see that ω = 8.4

Thus;

f = 8.4/(2π)

f = 1.337 Hz

(c) Formula for the total energy is given by;

E = m•ω²•A²/2

Plugging in the relevant values, we have;

E = (1.15)(8.40)²(0.650)²/2

E = 17.142 J

(d) we want to find the kinetic energy and potential energy when x = 0.360 m.

The formula for kinetic energy in this case is given by;

K = (1/2)•m•ω²•(A² - x²)

Thus;

K = (1/2) × (1.15) × (8.40)² × ((0.650)² - (0.360)²)

K = 11.884 J

Also, the formula for the potential energy in this case is given by;

U = (1/2)•m•ω²•x²

Thus;

U = (1/2) × (1.15) × (8.40)² × (0.360)²

U = 5.258 J

3 0

3 years ago

A 4.80 Kg watermelon is dropped from rest from the roof of an 18.0 m building. Calculate the work done by gravity on the waterme

Nonamiya [84]

Answer:

Work, W = 846.72 Joules

Explanation:

Given that,

Mass of the watermelon, m = 4.8 kg

It is dropped from rest from the roof of 18 m building. We need to find the work done by the gravity on the watermelon from the roof to the ground. It is same as gravitational potential energy i.e.

W = mgh

$W=4.8\ kg\times 9.8\ m/s^2\times 18\ m$

W = 846.72 Joules

So, the work done by the gravity on the watermelon is 846.72 Joules. Hence, this is the required solution.

7 0

3 years ago

From the concepts you have learned in this module, how are you going to assess

Daniel [21]

Answer:

Find the explanation below.

Explanation:

Earth is properly designed to support life. This is seen in the favorable temperature that supports life, the water cycle that recycles water for plant and animal life, the atmosphere, energy, and nutrients.

1. Temperature: The temperature which is regulated by the different weather conditions such as the rains, snows, dry seasons all help to maintain a stable condition for life.

2. Water: The water cycle through processes like evaporation, condensation, precipitation, helps to ensure that there is never a lack of water in the earth. The numerous water bodies like the seas, oceans, rivers, lakes, also provide a habitat for some living things. Water makes up 70% of the earth.

3. Atmosphere: The atmosphere is a mixture of gases in the right proportions that are necessary for life. Oxygen, Nitrogen, Carbon, etc are released and inhaled by man and other living things. They are also involved in so many biochemical reactions that help in metabolism and catabolism.

4. Energy: Energy generated from the sun and within the earth is stored in various forms and is always conserved. This energy is converted to different states such as the potential, chemical, kinetic, mechanical forms to get work done and to release heat.

5. Nutrients: Though cycles such as the carbon, nitrogen, oxygen, and phosphorous cycles, the earth maintains its stock of essential nutrients that help to sustain life.

6 0

3 years ago

An object is placed on a surface. A student tries to apply various combinations of forces on the object. Which pair of forces wi

AVprozaik [17]

Answer:

See Explanation

Explanation:

The question is incomplete, as there are no diagrams or options to provide more information to the question.

The general explanation is as follows:

For the object not to move

(1): The forces acting on the object must opposite each other. i.e. if force A acts at the right (or positive direction), force B will act at the left (or negative direction).

(2) The two forces must be equal.

So, for instance:

If the pair of forces are 5N and 5N in opposite directions, the object wil not move.

However, if one of the forces is greater, the object will move towards the direction of the greater force.

7 0

2 years ago