Answer:
Remember the relation:
Speed*Time = Distance.
Then first let's find the total distance that Hari drove.
First, he droves 2 hours at 60km/h, then the total distance traveled is:
Distance = 2h*60km/h = 120km
Then he droves 3 hours at 70km/h
The distance here is:
Distance = 3*70km/h = 210km
The total distance traveled is 120km + 210km = 330km
The total time of the travel is 2 hours + 3 hours = 5 hours.
The average speed is calculated as:
Av speed = (total distance)/(total time)
Av speed = (330km)/(5 h) = 66km/h
The average speed is 66km/h.
b) We know that the speed is 70km/h, but we want to write this in m/s.
Then we first know that 1 km = 1000m
then:
1 = (1000m/1km)
Then 70km/h = 70 km/h*(1000m/1km) = (70*1000) m/h = 70,000 m/h
Now we know that 1h = 3600 seconds, then:
1 = (1h/3600s)
So we can write:
70,000 m/h = (70,000 m/h)* (1h/3600s) = 70,000/3600 m/s = 0.019 m/s
and the distance is 135 km
Again, we can rewrite this as:
135km = 135km*(1000m/1km) = 135,000m
Then we want to solve:
(0.019m/s)*time = 135,000 m
We want to solve this for the time, then we get:
time = (135,000m)/(0.019m/s) = 7,105,263.2 seconds = 1.93 hours
The statement "If a plant receives fertilizer,
then it will grow to be bigger than a plant
that does not receive fertilizer" is an
example of
A. an observation.
B. a hypothesis.
C. a theory.
A human body consists of
Answer:
60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, the brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%.
Explanation:
How to calculate the voltage of a light bulb
An electric motor supplies 2,500 Watts of power in a 220 V circuit. What is the resistance of the motor? Be sure to include the proper units in your answer. Remember... Ω is the unit for Resistance.
Answer:
R = 19.36 ohms
Explanation:
Given that,
The power of an electric motor, P = 2500 Watts
The voltage of the circuit, V = 220 V
We need to find the resistance of the motor. We can find it as follows :
[tex]P=\dfrac{V^2}{R}\\\\R=\dfrac{V^2}{P}\\\\R=\dfrac{(220)^2}{2500}\\R=19.36\ \Omega[/tex]
So, the resistance of the motor is 19.36 ohms.
Find the velocity of a dolphin that swims 55 m in 5.0 s.
Answer: 11 m/s
Explanation: velocity = distance /time = 55 m /5.0 s
Answer:40km/h
Explanation:
Which phrase best completes the diagram?
Role of the Federal Reserve in the U.S. economy:
Sets interest rates➡️?➡️Loans money to other banks
A. Approves the federal budget.
B. Votes on coporate regulations.
C. Sets the consumer price index.
D. Makes rules for other banks.
Correct answer is:
D. Makes rules for other banks.
Answer:
B
Explanation:
i think
Answer:
D. makes rules for other banks
Explanation:
A police car drives with a constant speed of 70km/hr. how long will it take to cover a distance of 135km?
(btw, it's a physics question:-)
Explanation:
36. How long does it take a car to slow down from a speed of 54 km/h to 32 km/h over a distance of 65 m? Answer in seconds. 37.
PLEASE HELP ME WITH THIS ONE QUESTION
Two substances of different temperatures are brought into thermal contact. While the objects come to equilibrium, some heat is lost to the environment. How would that affect the final temperature?
A) it would be higher
B) it would change unpredictably
C) it would remain the same
D) it would be lower
Answer:
the correct is D
Explanation:
In the calorimetry exercises, if there are no losses, we assume that all the heat lost by one body is absorbed by the other, but if there are losses
Q_ {yielded} = Q_ {absent} + Q_ {lost}
Since energy cannot be created or destroyed, they only ask to change, therefore the term of the absorbed heat must decrease, consequently the final temperature of the system is lower when there is loss of energy.
When checking the answers, the correct one is D
What aquatic species is the least susceptible to acid rain? (Refer to the chart in the lesson to answer this question.)
a bass
b Baetis mayflies
c Bullfrogs
d Rainbow Trout
Answer:
c. Bullfrogs
Explanation:
I did this lesson and got it right! :)
To teach you how to find the parameters characterizing an object in a circular orbit around a much heavier body like the earth.
The motivation for Isaac Newton to discover his laws of motion was to explain the properties of planetary orbits that were observed by Tycho Brahe and analyzed by Johannes Kepler. A good starting point for understanding this (as well as the speed of the space shuttle and the height of geostationary satellites) is the simplest orbit--a circular one. This problem concerns the properties of circular orbits for a satellite orbiting a planet of mass M. For all parts of this problem, where appropriate, use G for the universal gravitational constant.
1. Find an expression for the square of the orbital period.
2. The quantities v, K, U, and L all represent physical quantities characterizing the orbit that depend on radius R. Indicate the exponent (power) of the radial dependence of the absolute value of each.
Answer:
a) T² = ([tex]\frac{4\pi ^2}{GM}[/tex]) r³
b) veloicity the dependency is the inverse of the root of the distance
kinetic energy depends on the inverse of the distance
potential energy dependency is the inverse of distance
angular momentum depends directly on the root of the distance
Explanation:
1) for this exercise we will use Newton's second law
F = ma
in this case the acceleration is centripetal
a = v² / r
the linear and angular variable are related
v = w r
we substitute
a = w² r
force is the universal force of attraction
F = [tex]G \frac{m M}{r^2}[/tex]
we substitute
[tex]G \frac{m M}{r^2} = m w^2 r[/tex]
w² = [tex]\frac{GM}{r^3}[/tex]
angular velocity is related to frequency and period
w = 2π f = 2π / T
we substitute
[tex]( \frac{2\pi }{T} ) = \frac{GM}{r^3}[/tex]
the final equation is
T² = () r³
b) the speed of the orbit can be found
v = w r
v = [tex]\sqrt{\frac{GM}{r^3} } \ r[/tex]
v = [tex]\sqrt{\frac{GM}{r} }[/tex]
in this case the dependency is the inverse of the root of the distance
Kinetic energy
K = ½ M v²
K = ½ M GM / r
K = ½ GM² 1 / r
the kinetic energy depends on the inverse of the distance
Potential energy
U =
U = -G mM / r
dependency is the inverse of distance
Angular momentum
L = r x p
for a circular orbit
L = r p = r Mv
L =
L =
The angular momentum depends directly on the root of the distance
Is there more than one way to get two objects with identical masses to balance? How?
Answer: yes you can
Explanation: because i i have a trying and a squar that have the same mass it would caunt as the same
Yes we can get two objects with identical masses to balance in this type of scenario.
What is Mass?
This is defined as the quantity of matter which is present in a body at a given point in time.
The two objects with identical masses can be made to balance through the use of a string and a pulley.
Read more about Mass here https://brainly.com/question/19385703
#SPJ9
PLEASE HELP ME WITH ONE QUESTION
If 1000 J of heat energy is lost from a piece of hot metal which is placed into a cup of cool water, how much energy is gained by the water?
Answer:
1000J
Explanation:
According to the law of calorimetry;
Heat lost by cold substance = Heat gained by hot substance
If 1000 J of heat energy is lost from a piece of hot metal,
heat lost by hot substance = 1000J
Since we are to determine how much energy is gained by the water, using the law
Heat lost by hot metal = heat gained by the water
Hence heat gained by the water = 1000J
1. Why is the flow of electrons from A to B?
2. What's the difference between flow of current & flow of electrons and why ar they opposite?
1. because A is more negative than B. A is -1000 V (we can imagine that A has excess 1000 electrons), in other, B which +3000 V can be assume that B need 3000 elctrons to be neutral. So, the electron will flow from A to B.
2. Electrons being negatively charged flow from the negative terminal to the positive terminal of the voltage source. So, the actual direction of current should be from negative to positive terminal. However, the conventional direction had already been established. So, the current flow is considered in the direction opposite to the direction of flow of electrons. (from topperlearning dot com)
A uniform 140 g rod with length 57 cm rotates in a horizontal plane about a fixed, vertical, frictionless pin through its center. Two small 30 g beads are mounted on the rod such that they are able to slide without friction along its length. Initially the beads are held by catches at positions 11 cm on each sides of the center, at which time the system rotates at an angular speed of 23 rad/s. Suddenly, the catches are released and the small beads slide outward along the rod. Find the angular speed of the system at the instant the beads reach the ends of the rod. Answer in units of rad/s.
Answer:
The correct answer is "12 rad/s"
Explanation:
The given values are,
Mass of rod,
M = 140 g
i.e.,
= 0.14 kg
Length,
L = 57 cm
i.e.,
= 0.57 m
Mass of beads,
M = 30 g
i.e.,
= 0.03 kg
Angular speed,
r = 11 cm
i.e.,
= 0.11 m
Now,
The inertia of rods will be:
= [tex]\frac{1}{12}ML ^2[/tex]
On substituting the values, we get
= [tex]\frac{1}{12}\times 0.14\times (0.57)^2[/tex]
= [tex]0.0037905 \ kg-m^2[/tex]
The inertia of beads will be:
= [tex]mr^2[/tex]
On substituting the values, we get
= [tex]0.03\times (0.11)^2[/tex]
= [tex]0.000726 \ kg-m^2[/tex]
The total inertia will be:
= [tex]Inertia \ of \ rods+Inertia \ of \ beads[/tex]
= [tex]0.0037905 + 0.000726[/tex]
= [tex]0.0045165 \ kg-m^2[/tex]
now,
The angular speed of the system will be:
⇒ [tex]L_1w_1=L_2w_2[/tex]
On substituting the values in the above equation, we get
⇒ [tex]0.0045165\times 23 = (0.0037905 + (0.03\times 0.285^2)\times 2 )\times w_2[/tex]
⇒ [tex]0.1038795 = 0.0037905 + (0.00243675\times 2 )\times w_2[/tex]
⇒ [tex]w_2 = 12 \ rad/s[/tex]
A projectile is thrown with a velocity of 40 m/s, 45 degrees above the +x-axis. Determine its initial x-velocity and its initial y-velocity.
x-component is V·cos(angle)
y-component is V·sin(angle)
When the angle is 45°, its sin and cos are both 1/2·√2 .
Vx = 20·√2 = 28.28 m/s
Vy = 20·√2 = 28.28 m/s
1. Only about
% of water on Earth is fresh water that is readily available for human consumption.
a. less than 1
b. 5
c. more than 50
d. All water on Earth is fresh water and is easily accessible.
Answer:
Hey mate.....
Explanation:
This is ur answer....
a. Less than 1%3% of the earth's water is fresh. 2.5% of the earth's fresh water is unavailable: locked up in glaciers, polar ice caps, atmosphere, and soil; highly polluted; or lies too far under the earth's surface to be extracted at an affordable cost. 0.5% of the earth's water is available fresh water....
Hope it helps you,
Mark me brainliest plz....
Follow me! :D
Question:
1. Only about % of water on Earth is fresh water that is readily available for human consumption.
a. less than 1
b. 5
c. more than 50
d. All water on Earth is fresh water and is easily accessible
Answer:
a. less than 1
How do sociologists view the categories of race, class, and gender?
Multiple Choice
1. inherent and inevitable
2. socially constructed
3. unchangeable and perpetual
4. natural and biologically determined
Answer:
2. Socially constructed
Explanation:
help, it's an emergency !!!!!!!
Chromosomes _____.
carry thousands of genes
can be analyzed in a karyotype
always occur in pairs
are tight coils of DNA
are carried on genes
Answer:
The correct answer for this would be D.
Explanation:
Are tight coils of DNA
The microwaves produced inside a microwave have a wavelength of 12.0m and a frequency of 25Hz. At what speed do the microwaves travel in units of m/s ?
Answer: 300 m/s
Explanation:
The equation for finding wave speed is the wavelength times the frequency which would be
12.0mx 25hz=300m/s
Charging by Contact examples
Answer:
the hair and the comb are both neutral
Gaseous sulfur dioxide is a compound that combines with water in the atmosphere to form acid rain. What is the primary source of sulfur dioxide?
O volcanic emissions
O combustion of fossil fuels
O destruction of tropical forests
O mining and mineral extraction
given that two vectors A=i,2j-2k and B=6i+3j+2k find A +B
Answer:
7i, 5j, 0k
Explanation:
Add up the two vectors.
Add
i+i 1+6 = 7i
j+j 2+3 = 5j
k+k -2+2 = 0k
therefore A+B = (7i, 5j, 0k)
PLZ HELP PLZ ILL GIVE BRAINLIEST TO BEST ANSWERED
The Earth's gravity pulling on a skydiver: Contact or Non Contact
Friction from a car's brakes causing it to stop: Contact or Non Contact
The repulsive magnetic force between the north poles of two magnets: Contact or Non Contact
The attractive electrostatic force between an electrically charged balloon and a wall: Contact or Non Contact
Answer:
1.Contact because its a contact force
2 Contact because when the car is stopping it is coming in to contact with the ground.
3 non Contact because magnets don't need to have contact they pull
4 non Contact because its not a contact force
who compose the Ghana national anthem
Answer:
Philip Gbeho
Explanation:
An elevator motor in a high-rise building can do 3500 kJ of work in 5 min. Find the power developed by the motor. Explain if you can plz
Answer:
P = 11666.6 W
Explanation:
Given that,
Work done by the motor, W = 3500 kJ
Time, t = 5 min = 300 s
We need to find the power developed by the motor. Power developed is given by :
[tex]P=\dfrac{E}{t}\\\\P=\dfrac{3500\times 10^3}{300}\\\\P=11666.7\ W[/tex]
So, the required power is 11666.6 W.
Two resistors R1 = 3 Ω and R2 = 6 Ω are connected in parallel. What is the net resistance in the circuit?
Answer:
2ohms
Explanation:
the net resistance is given by
1/R=1/R1 +1/R2,we are supposed to find R
thus by making R the subject ....
R=R1•R2/R1+R2
R=3•6/3+6
R=18/9 =2Ohms
Please help
The period of an oscillation is measured to be 0.0833 seconds. What is
the frequency of this oscillation? *
1.0833 Hz
0.287 Hz
9.8 Hz
12 Hz
0.007 Hz
Answer:
your
answer is
12.004
Please please help I'm stuck!!!
Answer: iDc im in 3grade
Explanation:sorry
Which types of reactions are also redox reactions?
Answer:
Your ans is B)
Explanation:
Hope its right
if wrong firgive me