A runner runs 400 metres in 1 minute 20 seconds. What is his speed in m/s​

Answer:

5m/s

Explanation:

400m/ 20+60s

= 400/ 80 m/s

5 ms-1

are dimensionless quantities always unitless​

A chemical lab isolates a gaseous element from the atmosphere that does not form chemical compounds. In which group of the periodic table is this element most likely found?

A. 18

B. 17

C. 1

D. 2​

Câu hỏi: Một bộ acquy có thể cung cấp một dòng điện 2 A liên tục trong 1 giờ thì phải nạp lại. Cường độ dòng điện mà acquy này có thể cung cấp nếu nó được sử dụng liên tục trong 5 giờ thì phải nạp lại là
0,4 A.
2,5 A.
2 A.
10 A.

9. A car of 1200 kg is rolling down a hill. When the car reaches a momentum of 7800 kg
m/s, what is its velocity?

what is the frequency of a wave that has a wavelength of 3m that is traveling at a speed of 9m/s

A 2.0 x 10^3 kg car moves down a level highway under the actions of two forces. One is a 1140 N forward force exerted on the wheels by the road. The other is a 950 N resistive force exerted on the car by the air. Use the work-kinetic energy theorem to find the speed of the car after it has moved a distance of 20.0 m, assuming the car starts from rest.

Trong thí nghiệm về giao thoa sóng trên mặt nước gồm hai nguồn kết hợp S1S2 cách nhau 15 cm với dao động với tần số 30Hz. Tốc độ truyền vòng 48 cm/s.
a. Tìm khoảng cách giữa hai cực đại gần nhau nhất.
b Tìm số điểm dao động với biên độ cực tiểu giữa S1S2.
c. Trong vùng giao thoa điểm M trên mái nhất cách S1S2 lần lược các khoảng MS1 =1,5 cm và MS2=7,9 cm. M là cực đại hay cực tiểu và là đường thứ bao nhiêu so với đường trung trực của S1S2.

What is the mass of the object if it has a density of 657 g/mL and a volume of 32 mL?
Show work!

When there is a horizontal wire, the needle of a compass placed beneath the wire comes to rest at right angles to the wire, pointing from left to right. In which direction will the compass needle point if it is held above the wire ? Explain your answer.

Urgent !
Will give the brainliest

Describe what it means to view something from a frame of reference.Give an example to illustrate your explanation.

The moment the skateboard starts moving (after skateboarder pushes it). Which of Newton's laws is most relevant to this action?

Hunger and thirst are examples of external stimulus true or false

Refer to the following illustration to answer this question.



Waves
To measure one wavelength, you would measure the distance between __________.
Question 16 options:


D and B


C and A


A and B


C and F

The air in a tire pump has a volume of 1.5 L at a temperature of 5 ℃. If the temperature is increased to 25 ℃ and the pressure remains constant, what is the new volume of the tire pump

You receive a generic email notification about an issue with the delivery of a recent order. You’re instructed to click on a link included in the email for further information about the order. When you click, it opens a webpage which asks for your account username and password before you can view the information. Which of the following is the biggest red flag in this scenario?
A. There is an issue while delivering your order.
B. The email you received was a generic notification.
C. The information about the delivery problems is not contained in the email.
D. Your username and password are required to view the information.

PLEASE ANSWER NEED HELP!!!!!!!! PLEASE THE CORRECT ANSWER!!!!!!


The brain itself does not contain nerves. How is it part of the central nervous system?
A.
It sends the signals out to the nerves.
B.
It is not—it is part of the endocrine system.
C.
Only parts of the body that move have nerves.
D.
It is a central part of the body, so it is in that system.


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explique o que você da frase:"não somos seres humanos passando por uma experiência espiritual... somos seres espirituais passando por uma experiência humana

Is the daughter or the science teacher correct? And why?

what is this it tastes sour
A. diamond
B. sugar
C. salt
D. cinnamon

At what distance will the weight of a body be halved , Earth's radius=6.4×10^6

How does alpha particles transfer energy to their surroundings?

Thea uses a hairdryer to dry her hair. The hairdryer has an efficiency of 0.5 and the total input energy is 180 kJ. How much of the energy supplied is wasted? Give your answer in joules

The moon goes around the Earth at an approximately constant speed, but not at a constant velocity. What difference would it make if it went in a constant velocity? Why doesn't it do so?

transivity, reflexivity, and identity refer to what kind of reasoning?

You used a telescope and other mathematics to discover that Jupiter is 5. 20 au from the sun. Use the equation to find its orbital period. Round to the nearest tenth of a year. Jupiter’s Orbit: years.

what is an emergent ray​

A race car traveling at 10 meters per second accelerates at a rate of 1.5 meters per second squared while travelling a distance of 600 meters. The final speed of the race car is approximately

A group of students is investigating whether wheels affect the force of friction. The students push two boxes each with the same force on a table. One box has wheels and the
other does not have wheels. The distance traveled by each box is shown.
Experimental Observations
Student 1 Student 2 Student 3 Student 4
Distance traveled by box with wheels
24 cm
22 cm
20 cm
23 cm
Distance traveled by box without wheels
12 cm
14 cm
15 cm
13 cm
Which step should the students take next?
Make a hypothesis
Test another variable
Analyze the results
Share their conclusion

NEED HELP!!! ANSWER THESE 5 QUESTIONS FOR 25 POINTS!!!! PLEASE ANSWER!! I WILL GIVE YOU BRAINLIEST

1. Therese plays lacrosse, but she has injured her ankle and has to take a few weeks off. She is finding that she has a lot of trouble sleeping since she is no longer practicing several days a week. What BEST explains this?
A.
She needs regular exercise to move oxygen through the blood.
B.
She clearly requires more exercise than most people to relieve stress.
C.
She is not releasing the endorphins that she used to, and that impacts her sleep.
D.
She is likely not maintaining the healthy habits that she did when she was practicing.


2. Imagine that you are running and want to track your heart rate. What is the easiest way to do this?
A.
Check your pulse at the wrist or neck.
B.
It can’t be done without special equipment.
C.
Close your eyes and count to 30 very slowly.
D.
Take off your shoe and check the top of your foot.


3. Guillermo has decided that he wants to be healthier, so he starts jogging. He has been at it for a week, but he is getting frustrated because he cannot run very far without getting out of breath. He is beginning to think that this is not a good exercise for him since he is not very good at it. What BEST explains why Guillermo is struggling?
A.
He probably does not have good form when he is exercising.
B.
He likely has heart or lung problems that he was not aware of.
C.
He does not have much endurance since he is new to exercise.
D.
He is just not good at jogging and needs to try something else.

4. Li Wei loves cardio and finds it very easy to fit into his schedule. Because he knows it is important to diversify his exercise routine, sometimes he runs and other days he rides his bike. What else should Li Wei consider regarding his routine?
A.
He should add some strength training.
B.
He needs to add one more form of cardio.
C.
He has too much cardio and should cut half of it.
D.
His program works for him, so he should not change it.


5. Jamar has decided that he is going to train for a marathon. He knows that it will take a lot of training, and that he will need to build his muscles. What part of the muscle does he need to build?
A.
oxygen levels
B.
fast twitch fiber
C.
slow twitch fibers
D.
large muscle mass


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how to find total internal reflection