Answer:
C.
Explanation:
Imagine you are running PE class. You run the first 1000 meters in 3 minutes and then get tired and run the last 600 meters in 5 minutes. What was your *average* speed?
Answer:
Va = 3.77 [m/s]
Explanation:
We know that speed is defined as the relationship between the distance traveled in a given time.
v = L/t
where:
v = speed [m/s]
L = distance = 1000 [m]
t = time = 3 [min] = 180 [s]
Therefore the first speed is:
v = 1000/180
v = 5.55 [m/s]
Now the second velocity:
t = 5 [min] = 300 [s]
v = 600/300
v = 2 [m/s]
The average speed is calculated by the sum of both speeds divided by two.
Va = (5.55 + 2) /2
Va = 3.77 [m/s]
a feather will fall through the air more slowly than a brick because of
Answer:
Air resistance
Explanation:
Because the air gives a much greater resistance to the falling motion of the feather than it does to the brick. The air is actually an upward force that is acting against gravity and slowing down the rate at which the feather falls.
A race car accelerates uniformly from 18.5 m/s to 46.1 m/s in 2.47 seconds.
Determine the acceleration of the car and the distance traveled.
Answer:
79.8 is the answere
I hope this HELP :)
Explanation:
Here, initial velocity is u=18.5m/s and final velocity is v=46.1m/s
Time taken t=2.47s
If a be the acceleration of the car.
Using v=u+at,
46.1=18.5+a(2.47)
⟹ a=11.17m/s
2
If d be the distance traveled by car.
Using formula v
2
−u
2
=2ad,
(46.1)
2
−(18.5)
2
=2(11.17)d
⟹ d=79.8m
A scientist claims that a certain chemical will make fabric waterproof. Which
option describes a controlled experiment that will produce evidence that will
support or refute her claim?
A. Two groups of fabric are treated with the chemical. One group is
cotton and the other is polyester. Then each group is exposed to
water.
B. One group of fabric is treated with the chemical, and the other
group is not. Then each group is exposed to water.
C. One group of fabric is treated with a small amount of the
chemical, and the other group is treated with a large amount. Then
each group is exposed to water.
O D. Two groups of fabric are treated with the chemical. Then one
group is exposed to a small amount of water, and the other group
is exposed to a large amount.
Answer:
B. One group of fabric is treated with the chemical, and the other group is not. Then each group is exposed to water.
Explanation:
What is the Net Force acting
on the box below?
kinetic energy is energy in the form of motin
Answer:
yes
Explanation:
HEY GUYS IS THIS TRUE OR FALSE????????
Question 18 (2 points)
A supersonic jet flying at 100 m/s is accelerated uniformly at the rate of 20 m/s2 for 20 s. What is its final velocity?
A 7 kg ball is moving at a constant speed of 5 m/s. A force of 300 N is applied to the ball for 4 s. The new speed of the ball is ?
Answer:
The new speed of the ball is 176.43 m/s
Explanation:
Given;
mass of the ball, m = 7 kg
initial speed of the ball, u = 5 m/s
applied force, F = 300 N
time of force action on the ball, t = 4 s
Apply Newton's second law of motion;
[tex]F = ma = \frac{m(v-u)}{t}\\\\m(v-u) = Ft\\\\v-u = \frac{Ft}{m}\\\\v = \frac{Ft}{m} + u[/tex]
where;
v is new speed of the ball
[tex]v = \frac{Ft}{m} + u\\\\v =\frac{300*4}{7} + 5\\\\v = 176.43 \ m/s[/tex]
Therefore, the new speed of the ball is 176.43 m/s
A falling object is said to reach a constant velocity (terminal velocity)..
a. when there is no gravitational force acting on it.
b. when there is no air resistance acting on it.
c. when air resistance equals the acceleration of gravity on it.
d. when it stops falling.
PLEASE HELP! thxssss
Answer:
D is correct
Explanation:
Una persona de 80 kg de masa corre a una velocidad cuya magnitud es de 9m/s. Cual es la magnitud de la cantidad de movimiento? Que magnitud de velocidad debe llevar una persona de 55 kg para tener la misma magnitud de la cantidad de movimiento que la persona de 80 kg?
Responder:
13,01 m / s
Explicación:
Paso uno:
datos dados
masa de la persona 1 m = 80 kg
velocidad de la persona 1 v = 9 m / s
masa de la persona 2 M = 55kg
velocidad de la persona 2 v =?
Segundo paso:
la expresión del impulso se da como
P = mv
para la primera persona, el impulso es
P = 80 * 9
P = 720N
Paso tres:
queremos que la segunda persona tenga el mismo impulso que la primera, por lo que la velocidad debe ser
720 = 55v
v = 720/55
v = 13,09
v = 13,01 m / s
Por lo tanto, la magnitud de la velocidad debe ser 13.01 m / s.
A baseball is thrown horizontally at a rate of 40m/s toward a home plate 18.4 m away. How far below the launch height is the ball when it reaches home plate
Answer:
1.03684mExplanation:
Using the formula for calculating range expressed as;
R = U√2H/g where
R is the distance moves in horizontal direction = 18.4m
H is the height
U is the velocity of the baseball = 40m/s
g is the acceleration due to gravity = 9.8m/s²
Substitute the given parameters into the formula and calculate H as shown;
18.4 = 40√2H/9.8
18.4/40 = √2H/9.8
0.46 = √2H/9.8
square both sides;
(0.46)² = (√2H/9.8)²
0.2116 = 2H/9.8
2H = 9.8*0.2116
2H = 2.07368
H = 2.07368/2
H = 1.03684m
Hence the ball is 1.03684m below the launch height when it reached home plate.
What is the typical response of people to a government that abuses them if they are used to that government?
Answer:
when a government abuses its power its called tyranny and people might try to overthrow the government
do you think it’s likely that there are other earth-like planets in our universe?
Answer:
yes it's a matter of probability
Answer:
Absolutely!
Explanation:
Its almost impossible that we are the only goldilocks planet when there are billions of stars, each of them being suns with planets. Some other planet somewhere must be able to support life, don't you think?
an atom's nucleus contains three protons and three neutrons what is the overall charge of the nucleus
Answer:
Positive
Explanation:
Because there is no electrons.
A model rocket accelerates at 15.3 m/s2 with a force of 44 N.
Calculate the mass of the rocket. Round your answer to the nearest tenth of a kg.
The mass of the rocket is
kg.
Answer:
The answer is 2.88 kgExplanation:
The mass of the object can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{44}{15.3} \\ = 2.875816...[/tex]
We have the final answer as
2.88 kgHope this helps you
Answer:
2.9
Explanation:
In the equation you get 2.88 but you round that to the nearest tenth so you get 2.9
5. Suppose you have three identical drinking cups: one made of plastic, one foam, and one paper.
You want to find out which cup will keep your hot cocoa hot for the longest time.
a. Phrase a formal question for this experiment.
b. What is your hypothesis?
c. What is the experimental variable?
d. What are three important control variables?
e. What type of evidence will you collect to test your hypothesis?
f. Challenge: Conduct your experiment and summarize your findings.
Answer:
a) How the cooling speed changes with glasses of different materials?
b) The glass material influences the cooling rate
c) temperatures initial, final and the time
d) the control variable is time
e)temperature of the beverage heated in a given time
f) best material for insulation was expanded
Explanation:
This is a problem of how to formulate an experiment using the scientific method
a) a question for this problem to follow.
How the cooling speed changes with glasses of different materials?
b) the hypothesis of the experiment is:
The glass material influences the cooling rate
c) we have the independent variable that the experimenter controls
the material of the glass, the initial temperature of the drink and the cooling time
the dependent variable is the one that is measured
the temperature of the drink and the time
d) the control variable is time
e) the evidence would be the temperature of the beverage heated in a given time
f) When conducting the experiment, the thermal conductivity of the material is the most important factor, the one with the lowest thermal conductivity is the one that keeps the drinks longer
in general, the conductivity ends of paper 0.24 W/m K and that of plastic is 0.06 W / m K, of expanded 0.03 W / m K
From these values it is experienced that the best material for insulation was expanded
1. A force acting on an object in the upward direction is 3 N. The force that would
balance this force could be written as
will balance because 3 N + (____
-) =
acts in the
direction.
You that know these forces
The balancing force
Answer:
See the explanation below
Explanation:
We must perform a sum of forces on the body, that sum of forces is equal to zero. That is, the body is in balance and does not move.
ΣF = 0
3 - 3 = 0
This force is negative and acts by pointing downwards.
Answer: ow consider a book sliding from left to right across a tabletop. Sometime in the prior history of the book, it may have been given a shove and set in motion from a rest position. Or perhaps it acquired its motion by sliding down an incline from an elevated position. Whatever the case, our focus is not upon the history of the book but rather upon the current situation of a book sliding to the right across a tabletop.
Explanation:
EARTH SPACE SCIENCE.
I NEED HELP ASAP DUE TODAY. PLEASE 20 POINTS
Using the topographic map above, match the description to the letter that it represents.
Highest point on the map-
[ Select ]
Stream flowing to the East-
[ Select ]
Letter near the steepest slope-
[ Select ]
Letter near the flattest area-
[ Select ]
Stream flowing to the North- F
Answer:
c,e,f,d
Explanation:
Someone help me plz. I have no idea.
Answer:
fault im pretty sure
Explanation:
Answer:
fault............
...........
Someone please help me Im confuzled.
its a solid from the pressure they put on a tennis ball would make it full of moving at fast speed matter bites compacted together but still moving.
By studying ____________________ scientists have learned about the layers of the Earth.
Answer: By studying seismic waves scientists have learned about the layers of the Earth.
3. A ball rolls along the floor with a constant velocity of 12 m/s. How far will it have gone
after 6 seconds?
Answer:
the answer is 49 ms do yeah
Answer:
72
Explanation:
hehe
can someone pls help me with this?
A ball is thrown through the air.What condition(s) would enable the ball to continue in its state of motion?
A. a tailwind
B. a headwind
C. no air resistance or gravity
D. contact with another object
Answer:
C) No air resistance or gravity
Explanation:
For headwind imagine an airplane flying. The wind is hitting the front of the aircraft. Just like the wind is hitting the front of the ball. This increases the drag force and the ball will eventually slow and let the force of gravity act.
For tailwind imagine a sailboat. The wind catches the sail a pushes the boat. Both the wind and boat are going the same way so the angle of the wind is coming from behind. This is why it is called a tail wind.
If a ball is thrown, it has wind resistance and gravity. Otherwise just imagine the ball traveling all around the earth. Because the ball only has the force of lift and thrust, the ball will stay in motion until it hits something strong enough to counteract its thrust.
The description does not state any contact with another object. Also the ball will immediately stop if it has less newtons of force.
ALWAYS use significant figure rules. Remember that these rules apply to all numbers that are measurements.
In working this problem, assume the value of "g" to be 9.8 m/s2 with two (2) significant digits unless otherwise stated.
A machine exerts a 100 N force to the right over a 5.00 meter length in 4.00 seconds. Calculate the power output of this machine.
_____ W
500.
125
80.0
0.200
Answer:
The answer is 500
Explanation:
I need help with physics
Answer:
mass (m) = 0.075 kg
acceleration (a) = 550000 m/[tex]s^{2}[/tex]
F = ( 0.075 kg )( 550000 m/[tex]s^{2}[/tex] ) = 41250 N
Explanation:
F = ma ; force is equal to mass times acceleration
mass (m) = 0.075 kg
acceleration (a) = 550000 m/[tex]s^{2}[/tex]
F = ( 0.075 kg )( 550000 m/[tex]s^{2}[/tex] ) = 41250 N.
do you get these options in the drop down?
help me, please!!!!!!
Answer:
Explanation:
The highest surface part of a wave is called the crest, and the lowest part is the trough. The vertical distance between the crest and the trough is the wave height. The horizontal distance between two adjacent crests or troughs is known as the wavelength...
draw a rough sketch of india to show the densely populated states any two
Answer: Im questing this what your looking for
Explanation: