Answer:
Explanation:
average speed = 90 km / hr
Let the total distance be 2 d .
time required to cover the time = 2 d / 90
time taken to cover distance d at 50 km /h = d / 50
time required to cover the nd half = 2 d / 90 - d / 50
.02222 d - .02 d = .002222 d
speed required = d/2 / .002222d
1 / 2 x .002222
= 225 km /h .
A runner is jogging in a straight line at a steady vr= 7.3 km/hr. When the runner is L= 2.1 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 29.2 km/hr (4 times as fast as the runner). When the bird reaches the finish line, it turns around and flies directly back to the runner After this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. The bird repeats the back and forth trips until the runner reaches the finish line. How far does the bird travel from the beginning (including the distance traveled to the first encounter
Answer:
Explanation:
Time taken by jogger to travel the distance to finishing line = 2.1 / 7.3
= .28767 hr
Bird will keep flying for this time period
distance covered by bird = speed x time
= 29.2 x .28767 km
= 8.4 km .
20. Give an example of sublimation.
Answer:Explanation:
A common example of sublimation is the dry ice, heavy CO2.
What is better for measuring how hard you are actually working, Target Heart Rate or Rating of perceived exertion?
Answer:
Rating of percieved exertion
What are the highest energy level electrons of an atom called?
A ball is thrown horizontally from the top of
a building 51 m high. The ball strikes the
ground at a point 120 m from the base of the
building.
The acceleration of gravity is 9.8 m/s
2
.
Find the time the ball is in motion.
Answer in units of s.
If the time the ball is in motion is 3.22617 s
Find the initial velocity of the ball.
Answer in units of m/s.
Answer:
whattt
Explanation:
sorry dear I did not understandA loaf of bread bakes in an oven. The bread is on a rack about one foot above the heat source. However, the top of the bread cooks just as fast as the bottom. How is heat being added to the bread?
Answer:
the bread is getting heated from top and bottom because the oven is heated all over and the particles from the oven makes the bread's particles heat up and the bread will be done
Explanation:
i have the same answer
Answer:
The air is heated by the heat source in the oven. The hot air rises, surrounds the bread, and heats the bread on all sides.
Explanation:
22. Explain in detail what happens to particles before, during, and after vaporization.
Answer:
Vaporization occurs when a substance changes from a liquid to a gas. The molecules in a liquid are in constant motion while staying relatively close together due to intermolecular forces. When an increase in temperature occurs, the molecules' kinetic energy also increases. If a liquid is heated the particles are given more energy and move faster and faster expanding the liquid. The most energetic particles at the surface escape from the surface of the liquid as a vapor as it gets warmer. Liquids evaporate faster as they heat up and more particles have enough energy to break away.
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Technician A says that leather shoes offer more protection than canvas shoes. Technician B says that steel toed boots are essential to protecting your feet from injury. Which technician is correct?
A) Technician A only B) Technician B only
C) Both technicians A and B D) Neither technician A nor B
Answer: Both technicians A and B
Explanation:
Based on the scenario in the question, it should be noted that leather shoes offer more protection than canvas shoes and that steel toed boots are essential to protecting your feet from injury.
Leather shoes are more durable and offer better protection than canvas. The strength of the material that they're made from can help in offering extra protection which is necessary in an environment where there's possibility of accidents involving falling objects.
Also, for the people who work in a work environment with many heavy machines and equipments, it is vital to it on protective steel toed boots in order to prevent the workers from feet related injuries.
A 68 kg runner exerts a force of 59 N. What is the acceleration of the
runner?
0 m/s2
1.16 m/s2
4012 m/s2
0.87 m/s2
d) ≈ 0.87 m/s²
Explanation:Hi there !
Newton's second lawF = m×a => a = F/m
a = 59N/68kg
1 N = 1kg·m/s²
= (59kg·m/s²)/68kg
= 0.8676 m/s²
≈ 0.87 m/s²
Good luck !
a car travels 200m in 30 s and 400m in the next 90s. Whats the average speed?
Answer:
300m per minute or 5m per second
Is a cookie crumbling or in other words breaking a cookie a physical change?
Answer:
Yes it is a physical change
Explanation:
The cookie is still a cookie even when it has been broken apart, so it cannot be a chemical change. The cookie only changed physically.
The MSDS for chloroform indicates that it is a clear liquid that has a pleasant smell and substantial vapor pressure. People should avoid inhaling its vapors, and it is sensitive to light. Malik needs 10 mls of chloroform for an experiment.
According to this information, how should he safely pour the chloroform?
He should locate the chloroform stored in a transparent container in chemical storage and pour directly into his beaker from that location.
He should locate the chloroform stored in a transparent container in chemical storage and should take it to the fume hood to pour.
He should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
He should locate the chloroform stored in a dark container in chemical storage and pour directly into his beaker from that location.
Answer:
The correct option is the third option
Explanation:
Firstly, it must be noted that chemicals/reagents that are sensitive to sunlight are stored in dark/amber container in the laboratory. Hence, the chloroform can only be found in an amber/dark bottle.
Also, reagents/chemicals that release poisonous/offensive gases are handled in the fume cupboard in the laboratory. Thus, If Malik is going to pour the chloroform, he should pour it in a fume cupboard to avoid inhaling it because of the toxicity of it's vapor.
From the above explanation, it can be deduced that Malik should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
Answer:
He should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
Explanation:
Convert 6.6 meters to centimeters
Answer:
660 centimeters
Explanation:
There are 100 cm in 1 m. To convert from m to cm, multiply by 100.
[tex]6.6 \times 100 = 660[/tex]
There are 660 cm in 1 m.
Explain and reason why the the moon rotates around the earth every lunar cycle
Pls explain ASAP
Best answer will be marked as BRAINLIEST✨
Muscles covert chemicals energy int
Answer:
Mechanical energy
Explanation:
Mechanical energy is needed for movement of objects. Muscles convert chemical energy provided by the rest of the body to allow movement.
If a 100n force has a 60-degree angle pulling on a 10kg block for 5m, what's the work done on the object
Answer:
250J
Explanation:
Given parameters:
Force on block = 100N
Degree of pull = 60°
Mass of block = 10kg
Distance = 5m
Unknown:
Work done on the object = ?
Solution:
The workdone on a body is the force applied to move a body in a specific direction;
Workdone = force x distance cos Ф
Insert the parameters and solve;
Workdone = 100 x 5 cos 60°
Workdone = 250J
A tree is turned into sawdust is that physical change or chemical change?
Answer:
Physical change
Explanation:
A physical change can be reversible where the original form of the matter can be restored, or irreversible where the original form cannot be restored. Therefore, sawdust is a physical change.
A toy car, initially travelling in a straight line at 30.0 cm/s, slows down with a constant linear acceleration of 3.0 cm/s2. How much time passes before the toy car comes to a halt?
Answer:
10s
Explanation:
Given parameters:
Initial velocity = 30cm/s
Acceleration = 3cm/s²
Unknown:
Time it takes for the car to come to rest = ?
Solution:
To solve this problem, we apply the right motion equation;
Our final velocity - 0
So;
V = U + at
Since the car is slowing down, it will have a negative acceleration
Insert the parameters and solve;
0 = 30 + (-3) x t
-30 = -t
t = 10s
A student uses two identical balls to perform an investigation. The students throws ball a with a horizontal velocity from a height of 10 meters. At the same time another students drops ball b from the same height without horizontal velocity. Neglecting air resistance what can you expect to when the balls will land?
Answer:
Both objects will land at the same time
Explanation:
The ball projected with a horizontal velocity has a vertical component of velocity which is independent of the horizontal velocity. The horizontal component of the velocity enables the ball to travel a horizontal distance, s The initial component of the vertical download velocity is zero.
Similarly, the object dropped from the height above the ground has an initial vertical velocity zero.
Neglecting air resistance, objects falling near the surface of the earth experience the same acceleration due to gravitational force of the earth, g = 9.8 meters per second squared (9.8 m/s²). So the acceleration is the same for the objects, and consequently their velocity is also increasing at a constant rate. After some time, t, both objects would have been accelerated downwards to the same extent, and would thus land at same time, t.
How do you calculate the radius of a planets orbit with mass and time ?
Answer:
By observing the time between transits, we know the orbital period. Kepler's Third law can be used to determine the orbital radius of the planet if the mass of the orbiting star is known (R3=T2−Mstar/Msun, the radius is in AU and the period is in earth years).
Explanation:
hope this helps!
Which type of wave is not reflected by the ionosphere?
Answer:
skip zone
Explanation:
The level of toluene (a flammable hydrocarbon) in a storage tank may fluctuate between 10 and 400 cm from the top of the tank. since it is impossible to see inside the tank, an open-end manometer with water or mercury as the manometer fluid is to be used to determine the toluene level. one leg of the manometer is attached to the tank 500 cm from the top. a nitrogen blanket at atmospheric pressure is maintained over the tank contents. felder, richard m.; rousseau, ronald w.; bullard, lisa g.. elementary principles of chemical processes, 4th edition (page 81). wiley. kindle edition.
Complete Question
The complete question is shown on the first and second uploaded image
Answer:
When water is used the reading is [tex] R = 2281.6 \ cm [/tex]
When mercury is used the reading is [tex] R = 23.83 \ cm [/tex]
The best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
Explanation:
From the question we are told that
The length of the leg of the manometer to the top of the tank is d = 500cm
The toluene level where in the tank where the height of the manometer fluid level in the open arm is equal to the height where the manometer is connected to the tank is h =150 cm
The manometer reading is R
Generally at the point where the height of the open arm is equal to the height of the of the point connected to the tank ,
The pressure at the height of the both arms of the manometer corresponding to the base of the tank are equal
i.e [tex]P_1 = P_2[/tex]
Here [tex]P_1[/tex] is the pressure of the manometer at the point corresponding to the base of the tank and this is mathematically represented as
[tex] P_{atm} + P_1 = P_{atm} + P_t[/tex]
Here [tex]P_t[/tex] is the pressure due to the toluene level in the tank and in the arm of the manometer connected to the tank and this is mathematically represented as
[tex]P_t = \rho_t * g * h_i[/tex]
Here
[tex]\rho_t [/tex] is the density of toluene with value [tex]\rho_t = 867 kg/m^3 [/tex]
[tex]h_i[/tex] is the height of the connected arm above the point equivalent to the base of the tank , this mathematically represented as
[tex]h_i = d - h + R[/tex]
and [tex] P_2 [/tex] is the the pressure at the open arm of the manometer at the point equivalent to the base of the base of the tank and this is mathematically represented as
[tex] P_2 = \rho_f * g * h_f [/tex]
Here
[tex]\rho_f[/tex] is the density of the fluid in use , if it is water the density is
[tex]\rho_w = 1000 \ kg /m^3 [/tex]
and if it is mercury the density is
[tex]\rho_m = 13600 \ kg /m^3 [/tex]
[tex]h_f[/tex] is the height of the fluid in the open arm of the manometer from the point equivalent to the base of the tank which is equivalent the manometer reading R
So when the fluid is water we have
[tex] P_{atm} + \rho_t* g *(d - h + R) = P_{atm} + \rho_f * g * h_f[/tex]
=> [tex] \rho_t* (d - h + R) = \rho_w * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 1000 * R [/tex]
=> [tex] R = 2281.6 \ cm [/tex]
So when the fluid is mercury we have
[tex] \rho_t* (d - h + R) = \rho_m * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 13600 * R [/tex]
=> [tex] R = 23.83 \ cm [/tex]
The difference in the mercury reading for mercury due to the fact that they have different densities as we have seen in this calculation
So the best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
Which refers to the distance between two crests or two troughs on a transverse wave? wavelength amplitude frequency hertz
Answer:
Wavelength
Explanation:
The distance between two crests or two troughs on a transverse wave is known as the wavelength.
What is a wavelength?The wavelength of a periodic wave is its spatial period or the distance over which the wave's structure repeats. It's the distance between two adjacent corresponding points of the same phase on the wave, such as two adjacent crests, troughs, or zero-crossings, and it's a feature of both travelling and standing waves, as well as other spatial wave patterns.
As discussed above the wavelength, therefore, the distance between two crests or two troughs on a transverse wave is known as the wavelength.
Learn more about Wavelength:
https://brainly.com/question/13533093
Which statement accurately describes a balanced force?
Answer:
a balanced force is when two forces equal each other out and therefor the object is not in motion.
Explanation:
otd-2)A softball is thrown straight up into the air at 25 m/s. if it returns to the thrower after 5.0 seconds, how high did it go?
One way:
The ball returned to the thrower's hand after 5 seconds. It spent 2.5 seconds going up, and 2.5 seconds coming back down.
Use the formula Distance = (1/2) (acceleration) (time squared)
Distance = (1/2) (gravity) (2.5 sec)
Distance = (1/2) (9.8 m/s ²) (6.25 sec² )
Distance = (4.9 m/s²) (6.25 sec²)
Distance = 30.63 meters
Another way:
The thrower threw the ball straight up at 25 m/s.
It sailed upward for 2.5 seconds.
At the top of its trip, before it started falling, its speed was zero.
Its average speed was (1/2) (25+0) = 12.5 m/s
At an average speed of 12.5 m/s for 2.5s, the ball rose (12.5x2.5) = 31.25m.
(Why are the two answers different ?
Because if the ball was thrown straight up at 25 m/s, it would actually return to the thrower in 5.1 seconds, not 5.0 seconds.
So if you use the acceleration of gravity to solve the problem, you get one answer, but if you use 5.0sec to solve it, you get a slightly different one.)
what is measurement ?
Answer: Measurement is the assignment of a number to a characteristic of an object or event, which can be compared with other objects or events. The scope and application of measurement are dependent on the context and discipline. In the natural sciences and engineering, measurements do not apply to nominal properties of objects or events, which is consistent with the guidelines of the International vocabulary of metrology published by the International Bureau of Weights and Measures. However, in other fields such as statistics as well as the social and behavioural sciences, measurements can have multiple levels, which would include nominal, ordinal, interval and ratio scales.
Explanation:
Covert 1 mile to feet. Then convert to inches. Then covert to centimeters. How many centimeters are in a mile?
Answer:
160,934.4 cm or in other words *160,934*
Explanation:
1 mile = 5280 ft.
5280 ft. = 63360 in.
63360 in. = 160934.4
If a bicyclist travels at 15 km/h, how long will it take her to travel 30 km?
if an object is moving and it changes its position by 2 m in every 4 s starting from the origin, then the position vs. time graph will be
Answer:
a straight line with a positive slope
Explanation:
Can you pls answer the 2 questions
Answer:
1) False, since constant speed means constant velocity, but with constant direction as well. Velocity is speed with direction. When you move in a circle, there are boundaries which means that a constant moving speed will cause the object to veer(move in different directions) to maintain movement, If it doesn't veer, the object will deflect(rebound) off the surface due to friction, and impact force or depending on its physical bond of malleability or density.
2a) Create position vectors by drawing a ray from the center(origin) of the circle to each of your desired points, it's magnitude will be the radius(how convenient). Both of these vectors go from the center of the circle to the position on the circle. In general, the distance from the origin to a point is called the radius vector.
2b)