Saturday, April 4, 2020

Normal Heart Rate free essay sample

In a long distance race, the athletes take four rounds of a track such that the time of Finish is same as the line of start. The length of the track is 200 m. a) What is the total distance covered by the athletes? b) What is the displacement when they touch the finish line? c) Is the motion uniform or non-uniform? d) Is the displacement and distance moved by the athletes at the end of the race equal? Why? 8. A man walks 5m in north direction and turns left to move 12m. What is the a) Distance, b) Displacement associated with the movement? 9. A man keeps 12 steps in north direction and turns right to keep 5 steps. He then returns to the initial point by the shortest path. Find a) Distance travelled. b) Displacement. Given step is 0. 4m. 10. A circular cycle track has a circumference of 308m (ABCDA) with AC as one of its diameter. We will write a custom essay sample on Normal Heart Rate or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page A cyclist travels from A to D along the circular path. Find the distance moved by the cyclist and the displacement if AB is along west-east direction. B A A C D 11. If 5m/s and 10m/s are the velocities of a body having a uniform acceleration in some time interval, what will be its average velocity? 2. A train travels from station A to station B with a speed of 36km/h and returns to A with a speed of 54km/h. What is the average velocity and average speed of travel? 13. A car travels with a velocity of V1m/s for S-m and with V2m/s for another S-m. What is the average velocity in the straight-line motion? 14. A train travels at a speed of 60 km/h for 0. 52h, at 30km/h for the next 0. 24h and then at 70km/h for the next 0. 71h. What is the average speed of the train? PROBLEM SOLVING ASSESSMENT Passage 1 We define power as the rate at which work is done. The power spent by a source is measured as the amount of work done per sec by a source or it is numerically equal to the work done by a source in one second. It is a scalar quantity If a lift takes 1 minute to lift ‘a’ load to another floor, while another lift ‘b’ takes 2 minutes to lift the load to the same floor, then work done by both the lifts would be same, but the power spent by lift ‘a’ is twice the power spent by ‘b’ because work is done at a faster rate by lift ‘a’. 1. On which of the following factors does power depend? A) Work B) Temperature C) Time D) Inertia 2. Ajay can transfer a suitcase which weighs about 35 kg, from one room to another in 10 sec. Vijay does the same job in 30 sec. which of the following statements is correct? A) Power spent by Ajay is thrice Vijay B) Power spent by Vijay is thrice the power spent by Ajay C) Both have spent equal powers. D) None of these. 3. If work is represented by u, temperature by v, momentum by x, time taken by y, and power by z, which one of the following is correct? A) Z=uvx/y B) Z=ux/y C) Z=xy/uv D) Z=u/y 4. Calculate the power of the engine which does a work of 5500 j in two minutes and 5 seconds. A) 44 W B) 44. 5 W C) 73 W D) 110 W Passage 2 A long time ago, a boy, later became one of the greatest scientists who dominated several fields, was wondering why should an apple fall from the tree when it gets detached. He was none other than Sir Isaac Newton. He ultimately established that earth, we live on, has a strange effect of attracting any object in the air. This property is known as gravitational force of earth. Hence an object at any height starts falling if it does not have any support. In other words, for an object at any height, lack of support can only be the reason for falling, it does not require any other force  and such act of any object is termed as ‘Free Fall’. A free fall is a downward motion without any initial force or velocity. Our earth has the inherent property of attracting items towards it. Hence a free fall is a natural phenomenon on earth for any object at any height without any support. Equations of free fall follow from equations of uniformly accelerated motion. These are- V= u+at S=ut+1/2 at2 V2-u2=2as. However ‘a’ is replaced by ‘g’ : A coin and a block of iron dropped from the same height and at the same time. Which one will first reach the ground? A) Coin B) Iron block C) Both reach at the same time D) Can’t be decided 2: An object is dropped from the top of a building and it hits the ground in 3 seconds. What is the height of the building? (assume g=9. 8 m/s2) A) 4. 41 m B) 44. 1 m C) 0. 441 m D) 44. 1 km 3: The acceleration due to gravity for a freely falling body is independent of which of the following parameters? A) Mass of the object B) Mass of earth C) Gravitational constant D) Radius of earth : which of the following is the correct relation between the time and height of free fall? a) v2h/g b) (2h/g)2 c) h/2g d) vh/2g Chemistry 1. Ordinary water boils at 1000c. Can it be made to boil at 950c or 1050c 2. What is the difference between a gas and a vapour? 3. Two cubes of ice are pressed hard between palms, When the pressure is released, the two cubes join together. Explain. 4. The Flame under a pressure cooker is suddenly put off. The whistle is suddenly removed to release the steam and the lid is forcibly opened you See water still boiling in the cooker even when no flame is underneath it. Explain Why? 5. A student spilled a bottle of ammonia in one corner of the laboratory. Soon the whole laboratory was filled with pungent irritating smell. The students immediately opened the windows and doors. After sometime students got relief. Answer the following questions? a) Why was the lab. filled with pungent irritating smell? b) Which property of particles is responsible for it? c) Will students get the smell if a bottle of HCl is spilled ? Give reason for your answer. 6. It is observed that water boils at lower temperature at higher altitude. Why? 7. Why butter is kept wrapped in a wet cloth when no refrigeration is available? 8. Why do we feel uncomfortable when humidity is very high? 9. What will happen to the melting point of ice if some common salt is added to it? Justify your answer. 10. .Explain how a human body maintains a constant temperature of about 37? C even when the outside temperature may be as high as 47? C. Plot a graph between temperature and time for the change from ice at -15? C to water to steam. Biology PSA QUESTIONS I. Read the given passage carefully and answer the questions that follow. PHOTOSYNTHESIS Photosynthesis(Gk. photos- light,synthesis-putting together)is an enzyme regulated anabolic process of manufacture of organic compounds inside the chlorophyll containng cells from carbon dioxide and water with the help of sunlight as a source of energy. A simple equation photosynthesis is as follows: 6CO2+6H2O(C6H12O6+6O2 However, the function of water is to provide hydrogen for th synthesis of organic compounds. All the liberated oxygen comes from it. Therefore, the equation is modified as 6CO2+12H2(C6H12O6+6H2O+6O2 The organisms which perform photosynthesis are called photoautotrophs. They include green plants ,red algae,brown algae, yellow green algae,several types of protists,cyanobacteia and some bacteria. Phototropic bacteria employ hydrogen donor other than water. Therefore,photosynthesis is also defined as an enzyme mediated anabolic process of manufacture of organic compounds inside the chlorophyll containing cells from carbon dioxide and hydrogen donor with the help of radiant energy. a)The process of photosynthesis is unique to: 1. Green plants 2. Bacteria 3. Phototrophs 4. Brown algae )All flesh is grass means 1. All animals are herbivores 2. All animals consume grass at least once in their life time. 3. All animals and heterotrophic plants depend upon the phototrophs for their organic food. 4. All heterotrophs are green. c)All life is bottled sunshine means 1. Living organisms shine. 2. Energy to carry out life activities ,is provided to all living beings by the Sun through photosynt hesis. 3. All living organisms photosynthesize 4. All living organisms convert solar energy into chemical energy d)An Anabolic process is the one which 1. Makes use of sunlight . An organic compound like glucose or starch is manufactured 3. Occurs in green plants only. 4. Carbon is involved II) Read the given passage and answer the questions that follow: ARTIFICIAL RESPIRATION Persons who have stopped breathing because of drowning ,electric shocks, or smoke inhalation may be subjected to artificial breathing until their own breathing can be initiated. A variety of methods of artificial respiration have been practiced over the years, but the mouth to mouth breathing method is very common. In this method,the operator lifts the patient’s neck by placing a hand below it. The operator then closes the nostrils of the patient with fingers. The operator keeps his own mouth in front of the patient’s mouth and blows air into the mouth of the patient,then he releases the patient’s mouth to allow expiration by his lungs. This procedure should be repeated 10-15 times per minute. The operator should know that the tongue tongue of a patient has a tendency to fall into the back of the throat and obstruct the passage of air. Therefore, it is important to check that the tongue has been pulled forward before beginning artificial respiration. a)Artificial respiration is given to a person when: 1. He has lost a lot of blood after an accident 2. He has lost consciousness 3. He has stopped inhaling and exhaling 4. His heart has stopped working b)If the operator blows air in the patient’s mouth continuously at the rate of 50-60 times per minute,the patient may not regain his breathing because,the patient will 1. Be tired in the process 2. Not get enough oxygen Have a lot of carbon dioxide accumulated in his lungs,because of absence of exhalation. 4. Not be able to inhale. c)Mouth to mouth breathing method is the most common of all artificial respiration methods because: 1. It requires less complicated apparatus. 2. It always initiates the patient’s breathing without fail 3. It can be done easily in emergency conditions as it doesn’t require any special apparatus or training 4. It always giv es the desired results within few seconds III)Read the given passage and answer the questions that follow: Pulse per minute is called the heart rate. As we know human heart beats about 72 times per minute in an adult person at rest,this is the heart rate of that person. The heart rate increases during exercise,fever and anger. Heart rate of smaller animals is higher than larger animals. The smaller animals also have a higher metabolic rate. An elephant has normal heart rate of about 25per minute whereas mouse has a normal heart rate of several hundreds per minute. a)If the heart rate of a person increases,his 1. pulse rate decreases 2. pulse rate also increases. . pulse rate remains the same. 4. pulse rate can’tbe measured b)If a person suffers some enlargement of heart, 1. He will die immediately. 2. His heart muscles will stop working. 3. His heart rate will increase. 4. His pulse rate will decrease. HOTS QUESTION Q 1. Which cell organelle has its own chromosome and ribosome and present in both plant and animal cell. What role does it play in cellular respiration? Also draw it well labeled diagram. Q 2. Why an egg shrinks when placed in concentrated salt solution?. Q 3. On what basis endoplasmic reticulum has been differentiated into two types? Q 4. Which cell organelles resemble following? 1. Kitchen of plant 2. Storage organ 3. Brain Q 5. A boiled egg was deshelled and then kept in water. What will happen? Q 6. How lysosomes resemble immune system? Q 7. How osmosis is a special case of diffusion? Q 8. Can a cell without nucleus (its nucleus is removed) work properly? Q 9. Does photosynthesis takes place in animal cells? Why plastids are necessary for photosynthesis? Q 10. Why plant cells cannot change their shape?

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