Answer:
We can write S = v * t where S is the distance traveled in time t
S = .12 rad/sec * 30 sec = 3.6 rad distance traveled
Also 2 * pi * N = S since there are 2 * pi rad / revolution
So 2 * pi * N = 3.6
N = 3.6 / (2 * pi) = .573 revolutions
A piece of wood that floats on water has a mass of 0.0175 kg. A lead sinker is tied to the wood, and the apparent mass with the wood in air and the lead sinker submerged in water is 0.0765 kg. The apparent mass with both the wood and the sinker both submerged in water is 0.0452 kg. What is the SG of the wood
Answer:
The specific gravity of the wood is 1.56
Explanation:
Given;
mass of the wood in water, [tex]M_w_{H_2O}[/tex] = 0.0175 kg
apparent mass of the wood and lead sinker submerged in water, [tex]M_w_{(air)} + M_s_{H_2O}[/tex] = 0.0765 kg
apparent mass with both the wood and the sinker both submerged in water, [tex]M_w_{H_2O} + M_s_{H_2O} = 0.0452 \ kg[/tex]
Mass of the lead sinker alone submerged in water;
[tex]M_w_{H_2O} + M_s_{H_2O} = 0.0452 \ kg\\\\0.0175 \ kg + M_s_{H_2O} = 0.0452 \ kg\\\\M_s_{H_2O} = 0.0452 \ kg - 0.0175 \ kg\\\\M_s_{H_2O} = 0.0277 \ kg[/tex]
Mass of the wood in the air;
[tex]M_w_{(air)} + M_s_{H_2O} = 0.0765 \ kg\\\\M_w_{(air)} + 0.0277 \ kg = 0.0765 \ kg\\\\M_w_{(air)} = 0.0765 \ kg - 0.0277 \ kg\\\\M_w_{(air)} = 0.0488 \ kg[/tex]
Mass of water is calculated as follows;
[tex]M_w_{(air)} - M_w_{H_2O} = M_{H_2O}\\\\0.0488 \ kg - 0.0175 \ kg = M_{H_2O}\\\\0.0313 \ kg = M_{H_2O}[/tex]
The specific gravity of the wood is calculated as follows;
[tex]Specific \ gravity\ (S.G) \ of \ wood = \frac{mass \ of \ wood\ in \ air }{mass \ of \ water} \\\\Specific \ gravity\ (S.G) \ of \ wood = \frac{0.0488}{0.0313} \\\\Specific \ gravity\ (S.G) \ of \ wood = 1.559 = 1.56[/tex]
Therefore, the specific gravity of the wood is 1.56
Prominences and sunspots are both:
A. Jets of burning gas
B. Patches on the Sun's surface
C. Influenced by the Sun's electromagnetic field
D. Visible during an eclipse
Answer:
C. Influenced by the Sun's electromagnetic field
Explanation:
"Sunspots occur in pairs because each is one side of a loop of the Sun's magnetic field that reaches the Sun's surface. Solar prominences are the plasma loops that connect two sunspots."
please help asap
Ms. Brando’s students are studying forces. She has assigned a fun task: designing a balloon car. The students must design a car and see which model will travel the greatest distance. The basic design of the cars can be seen here. First the balloon is inflated and attached to the car. It is important to keep the balloon closed. Once attached to the car, the stem of the balloon is opened and air rushes out through the straw. The air goes one way; the car moves in the other direction. There are no restrictions on the design other than the students must use the materials given to them by Ms. Brando. What is the source of the force that moves the car? A) The circumference of the balloons. B) The friction between the wheels and the track surface. C) The air rushing out of the balloon through the straw. D) The mass of the car: the lighter the car the farther it moves.
Answer: a
Explanation:
when a car dives on a road it a makes friction but it need something to push it or start it which is the balloon in this example
(sorry if im wrong)
A disk of a radius 50 cm rotates at a constant rate of 100 rpm. What distance in meters will a point on the outside rim travel during 30 seconds of rotation?
Answer:
the distance in meters traveled by a point outside the rim is 157.1 m
Explanation:
Given;
radius of the disk, r = 50 cm = 0.5 m
angular speed of the disk, ω = 100 rpm
time of motion, t = 30 s
The distance in meters traveled by a point outside the rim is calculated as follows;
[tex]\theta = \omega t\\\\\theta = (100 \frac{rev}{\min} \times \frac{2\pi \ rad}{1 \ rev} \times \frac{1\min}{60 s} ) \times (30 s)\\\\\theta = 100 \pi \ rad\\\\d = \theta r\\\\d = 100\pi \ \times \ 0.5m\\\\d = 50 \pi \ m = 157.1 \ m[/tex]
Therefore, the distance in meters traveled by a point outside the rim is 157.1 m
Two masses are connected by a string which passes over a pulley with negligible mass and friction. One mass hangs vertically and one mass slides on a horizontal surface. The horizontal surface has a coefficient of kinetic friction of 0.200. The vertically hanging mass is 3.00 kg and the mass on the horizontal surface is 3.00 kg. The magnitude of the acceleration of the vertically hanging mass is (the initial velocity of the horizontal mass is to the right)
Answer:
[tex]a=2,5m/s^2[/tex]
Explanation:
From the question we are told that:
Coefficient of kinetic friction [tex]\mu= 0.200[/tex]
Vertical Mass [tex]M_v=3kg[/tex]
Horizontal mass [tex]M_h=3.00kg[/tex]
Generally the equation for kinetic force [tex]F_k[/tex] is mathematically given by
[tex]F_k=\mu N\\F_k=0.2*3\\F_k=0.6[/tex]
Generally the equation for T is mathematically given by
[tex]For M_v=3kg3g-T=3a[/tex]
For [tex]M_h=3kg[/tex]
[tex]T=M_v V+F_k\\T=3.0a+0.6[/tex]
Therefore substituting
[tex]3-3a-0.6=3a\\2.4g=6a[/tex]
[tex]a=2,5m/s^2[/tex]
What is a positive effect of increased carbon dioxide within the carbon cycle?
Answer:
The positive impact in the cycle is that CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.
Explanation:
Carbon cycle is the process by which carbon dioxide travels from the atmosphere to the earth and returns back to the atmosphere.
The negative impact of carbon dioxide in the carbon cycle is that it will cause green house effect. However, when it comes to the positive impact in the cycle, CO2 will make plants to use water more efficiently and also thereby make them to become drought resistant and thereby grow faster.
Due to the earth's rotation, a person would be traveling faster at the equator than they would at a position halfway from the equator to the North Pole.
Answer:
False
Explanation:
It is actually the exact opposite.
Answer:
True.
Explanation:
Because the Earth's rotation causes it to bulge at the equator, the circumference of the Earth is greatest at the equator. This means that a person at the equator would have to travel a greater distance in a given amount of time than a person at a position closer to the poles. Therefore, a person at the equator would be traveling faster than a person at a position closer to the poles.
1.Calculate the energy transferred by a 12V hairdryer, running on a current of 0.50A, that is left on for 8.0 minutes.
2. f 4 coulombs of charge flows in the circuit with a p.d. of 15V. Calculate the total energy transferred.
3. A 6.0 V battery passes a current of 1.0 A through a lamp for 2 minutes. How much charge passed through the lamp.
Answer:
1. Energy = 2880 Joules.
2. Energy = 60 Joules.
3. Quantity of charge = 120 Coulombs.
Explanation:
Given the following data;
1. Voltage = 12 Volts
Current = 0.5 Amps
Time, t = 8 mins to seconds = 8 * 60 = 480 seconds
To find the energy;
Power = current * voltage
Power = 12 * 0.5
Power = 6 Watts
Next, we find the energy transferred;
Energy = power * time
Energy = 6 * 480
Energy = 2880 Joules
2. Charge, Q = 4 coulombs
Potential difference, p.d = 15V
To find the total energy transferred;
Energy = Q * p.d
Energy = 4 * 15
Energy = 60 Joules
3. Voltage = 6 Volts
Current = 1 Amps
Time = 2 minutes to seconds = 2 * 60 = 120 seconds
To find the quantity of charge;
Quantity of charge = current * time
Quantity of charge = 1 * 120
Quantity of charge = 120 Coulombs
Calculate the speed of an object that travels 75m in 15s.
Answer:
5m/s
Explanation:
speed=distance/time
=75/15
=5m/s
A car has a mass of 1200 kg and a velocity of 14 m/s. Calculate the
momentum of the car.
Answer:
p = 16,800
Explanation:
Before we make measurements, let's make sure we understand the circuit. 1. Select all of the following that correctly describe what a volt meter and ammeter measure. Select all that apply: A volt meter measures the potential difference (or voltage) across a circuit element. A volt meter measures the potential difference (or voltage) passing through a circuit element. A ammeter measures the electric current passing through a circuit element. A ammeter measures the electric current across a circuit element.
Answer:
the correct answers are a and c
Explanation:
In an electrical circuit there are two important quantities to measure, such as voltage and current.
Voltage is the potential difference between two points in a circuit
current is the number of electrons you pass through a given point per unit of time.
Now let's analyze each answer
a) true. The potential difference across an element
b) False. The potential difference is u field there is no physical entity that moves
c) True. The current is electrons in motion and these pass through the given element
d) False. There is a physical quantity that passes through the point
the correct answers are a and c
State Newton’s Universal Law of Gravitation.
Answer:
This law states that every particle attract every other particle in the universe with a force that is directly proportional to the product of their mass and inversely proportional to the square of the distance between the center
