Testing Online EMSS PDF

Extramarks Total Questions: 25 Time : 30 Mins Maximum Marks : 25 General Instructions All Questions are compulsory. 1. Sam's mother wants...

Extramarks Total Questions: 25 Time : 30 Mins Maximum Marks : 25 General Instructions All Questions are compulsory. 1. Sam's mother wants to teach him the concept of profit and loss. She buys some oranges at ₹ 10 for 4 and sold them at ₹ 27 for 4 and asked him to find the1 profit Mark a. 170 b. 382.5 c. 462.5 d. 370 Text Solution by our experts CP of 4 oranges = ₹ 10 CP of 1 orange = ₹ 104 SP of 4 oranges = ₹ 27 SP of 1 orange = ₹ 27 P rof it on 4 1 orange = ₹ ( 274 − 104 ) ( 27 − 10 ) P rof it percent = 4 10 4 × 100P rof it percent = 170 4 Board: Maharashtra-OLD | Class: VIII | Subject Name: Mathematics | Chapter: Chapter | Topic: Percentage | Unit: Arithmetic | Time to solve: 01:00 min | Question ID: 7221778 | Difficulty Level: Difficult | Question Type: Single Choice Question CBSE > VIII > Mathematics > Comparing Quantities > Profit, Loss and Compound Interest 2. _______. 1 Mark a. 19 b. 10 9 1 c. 27 1 d. 18 Text Solution by our experts x 729 = 3 x = 729 3 = 19 So, the value of x is 19. Board: CBSE | Class: VIII | Subject Name: Mathematics | Chapter: Chapter | Topic: Square Roots of Decimals and Estimation | Time to solve: 01:00 min | Question ID: 7227009 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Mathematics 3. An atom has atomic number 15. Valence electrons for this atom are 1 Mark a. 7 b. 5 c. 10 d. 9 Text Solution by our experts T he electrons present in the last shell are called valence electrons. Board: CBSE | Class: VIII | Subject Name: Science | Time to solve: 01:00 min | Question ID: 7260133 | Difficulty Level: Difficult | Question Type: Single Choice Question CBSE > VIII > Science 4. The pressure exerted by a body of mass 15 kg on an area of 6 ​ [Take g = 10 m/ ] 1 Mark a. 2.5 N b. 25 N  c. 12.5 N d. 250 N Text Solution by our experts Given, mass, m = 15 kgArea, a = 6 m2 F orce f , can be calculated by using the relation, F orce = mg F = 150 N P ressure p, can be calculated by using the relation, pressure = f orce/area P = 25 N m−2 Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Topic: Pressure | Time to solve: 01:00 min | Question ID: 7216396 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Force and Pressure > Pressure 5. 1 Mark A truck weighing 4 kN rests on 6 tires. Each tire has the contact area of 480 sq. cm. If at rest position, the truck is made to rest on 4 tyres then the pressure exert a. 20000.0 P a b. 1166.67 P a c. 1875.0 P a d. 2105.26 P a Text Solution by our experts F orce exerted by the truck is F = W = 4 kN. T he resting area of each tire is A = 480 cm2. In standard units the resting area of each tire = Area in contact with the ground = 0.05 m2. As the truck is made to rest on 4 tyres only , the total area of contact with the ground is 0.19 m2. P ressure exerted on the ground is given by P = FA Substituting the values we have P = FA = 20000.0 P a Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Topic: Pressure | Time to solve: 01:00 min | Question ID: 7216336 | Difficulty Level: Easy | Question Type: Single Choice Question CBSE > VIII > Science > Force and Pressure > Pressure 6. 1 Mark A bag weighing 35 kg weight is placed on a rectangular table of length 54 cm and breadth 69 cm. If the table and bag are left undisturbed then evaluate the press a. 0.01 N /m2 b. 9.38 N /m2 c. 0.94 N /m2 d. 94.59 N /m2 Text Solution by our experts T he f orce exerted by the bag here is 35 kg wt = 35 N T he area of the table surf ace is given by A = 0.37 m2 T he pressure acting on the table surf ace is given by P = FA Substituting the values of F and A we get P = FA = 94.59 N /m2 Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Topic: Pressure | Time to solve: 01:00 min | Question ID: 7216352 | Difficulty Level: Easy | Question Type: Single Choice Question CBSE > VIII > Science > Force and Pressure > Pressure 7. 1 Mark ​A student took four combustible substances I, II, III, and IV. He found that the ignition temperatures of I, II, III and IV are 45 °C, 37 °C, 55 °C and 95 °C respectively. a. IV b. II c. I d. III Text Solution by our experts It is the minimum temperature to which a combustible substance must be heated, bef ore it catches f ire. T heref ore, IV will not catch f ire. Board: CBSE | Class: VIII | Subject Name: Science | Time to solve: 01:00 min | Question ID: 7259986 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science 8. Coal produces energy on combustion. Which of the following will provide maximum energy on combustion? 1 Mark a. Coal gas b. Coal c. Coke d. Coal tar  Text Solution by our experts Correct Answer − Coke Explanation − Coke is almost the purest f orm of carbon. So, it burns with maximum eff iciency and provides maximum energy. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Topic: Coal | Time to solve: 01:30 min | Question ID: 7332240 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Coal and Petroleum > Coal 9. If 7 articles are sold for cost price of 9 articles, then the profit percentage is 1 Mark a. 1600 7 b. 100 7 c. 200 7 d. 900 7 Text Solution by our experts Let the CP of an article be ₹ 1. So, CP of 9 articles is ₹ 9.N ow, SP of 7 articles is ₹ 9.So, SP of 9 articles = ( 97 ) × 9= ₹ 81 7 So, prof it on selling of 9 articles = 81 18 2 7 − 9 = ₹ 7 prof it % = 7 × 100So, prof it % = 7 200 Board: Maharashtra-OLD | Class: VIII | Subject Name: Mathematics | Chapter: Chapter | Topic: Percentage | Unit: Arithmetic | Time to solve: 01:00 min | Question ID: 7223789 | Difficulty Level: Difficult | Question Type: Single Choice Question CBSE > VIII > Mathematics > Comparing Quantities > Profit, Loss and Compound Interest 10. Study the following information to answer the questions given below : 1 Mark (i) A, B, C, D, E, F and G are seven members of a family. (ii) There are two doctors, two teachers, two professors and one lawyer. (iii) No lady is either teacher or lawyer. (iv) Teacher's wife is a professor and lawyer's wife is also a professor. (v) C is the daughter-in-law of F and mother of E. (vi) B, a doctor, is son of G, and E, who is not a professor, is the daughter of lawyer. (vii) A's husband is a teacher and A is the mother-in-law of C and grandmother of B. (viii) F is the grandfather of B and D. How is D related to A ? a. ​Granddaughter​ b. ​Son​ c. Grandson​ d. ​Daughter​ Text Solution by our experts The information given for the questions suggest that all the seven members belong to three generations in the following way: 1(st ) generation Grandparents F (Male Teacher) A (Female Professor) 2(nd) generation Parents G (Male Lawyer) C (Female Professor) 3(rd) generation Children B (Male Doctor) E (Female Doctor) D (Male Teacher) Option ( C ) is correct. D is the grandson of A. Board: Foundation | Class: VIII | Subject Name: Mental Ability | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7376733 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Mathematics 11. Six people A, B, C, D, E and F are sitting on the ground in a hexagonal shape. All the sides of the hexagon so formed 1 Mark are of same length. A is not adjacent to B or C, D is not adjacent to C or E , B and C are adjacent, F is in the middle of D and C.  Which of the following is in the right sequence? a. A, F, B b. F, A, E c. B, C, F d. D, A, B Text Solution by our experts F is in the middle of D and C; B and C are adjacent; A is not adjacent to C. Thus, two seating arrangements are possible: Option (C) is correct. B, C, F are sitting in consecutive positions. Board: Foundation | Class: VIII | Subject Name: Mental Ability | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7376711 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Mathematics 12. Read the following information carefully and answer the questions given below. 1 Mark (i) In a family of six persons - P, Q, R, S, T and U - there are three gents and three ladies. There are two married couples and two persons are unmarried. Each one of them reads different newspapers, viz. The Times of India, Indian Express, Hindustan Times, Amar Ujala, Navbhart Times and The Hindu. (ii) T, who reads Indian Express, is mother-in-law of P who is wife of R. S is the father of U and he does not read The Times of India or The Hindu. Q reads Navbharat Times and she is the sister of U who reads Hindustan Times. R does not read The Hindu. How many sons does T have? a. ​One​ b. Two​ c. ​Three​ d. ​Four​ Text Solution by our experts T is mother-in-law of P and P is wife of R. So, R is P's husband and T is mother of R. So, one couple is RP. Since S is father of U, so S is the husband of T. So, the other couple is ST. Since, Q is sister of U, so R, U and Q are children of S and T. Since there are three gents in all, so U is also a male. Now, Q reads Navbharat Times, U reads Hindustan Times, T reads Indian Express. Since S does not read The Times of India or The Hindu, so S reads Amar Ujala. Since R does not read The Hindu, so R reads The Times of India. Clearly, P reads The Hindu. 1. Clearly, T has two sons -R and U. So, the answer is (B). Board: Foundation | Class: VIII | Subject Name: Mental Ability | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7376662 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Mathematics 13. Read the following information carefully and answer the questions given below. 1 Mark (i) A, B, C, D, E, F an G are sitting around a circle and are facing the centre. (ii) G is second to the left of C, who is to the immediate left of F. (iii) A is third to the left of E. (iv) B is between D and E. Which of the following is the position of F? a. Fourth to the right of D b. To the immediate left of C c. Between A and E d. To the immediate right of A  Text Solution by our experts We first of all mark the seven blank positions around a circle. Now, G is second to the left of C and C is to the immediate left of F. We mark their positions as shown below. Also, B is between D and E. Thus, D, B, E sit together and occupy the three consecutive blank positions. Now, only one position remains blank between G and C, and this must be occupied by A. Now, D, B, E may its in any of the positions ( D, B, E) or (E, B, D). But A is third to the left of E only when they its in the order ( D, B, E). Thus, we mark their positions as shown. 5. Clearly, F's position is (i) fourth to the right of D (ii) to the immediate right of C (iii) between C and E (iv) second to the right of A Hence, the answer is (A). Board: Foundation | Class: VIII | Subject Name: Mental Ability | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7376661 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Mathematics 14. A scientist performed an experiment in which he passed carbon dioxide gas into a water beaker. He observed that 1 Mark the gas was dissolved completely in water. Later, he inserted a blue litmus paper in the beaker, and he observed that the paper turned red. Select the correct observation regarding the experiment. a. A gas is formed during the reaction. b. A salt is formed during the reaction. c. A base is formed during the reaction. d. An acid is formed during the reaction. Text Solution by our experts Carbon dioxide is completely soluble in water. When a blue litmus paper was inserted into the beaker, the paper turned red. Acids turn blue litmus paper red. It can therefore be concluded that carbon dioxide gas reacted with water to form an acid named carbonic acid. The water in the beaker was acidic in nature. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7285486 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Materials : Metals and Non-Metals 15. Stars appear to rotate from east to west due to the Earth’s rotation, except Polaris. But why? 1 Mark a. Polaris or the north star is present at the position that aligns with the Earth’s b. Polaris is visible from the northern hemisphere and stars do not appear axis of rotation. rotating along north south direction.  c. Polaris is present in the southern hemisphere where stars do not appear to d. Polaris is the part of the constellation Ursa Major which does not rotate at all rotate at all. when viewed from the Earth. Text Solution by our experts ​Polaris is located nearly directly above Earth's northern rotational pole. Therefore, when Earth spins, Polaris appears almost stationary in the sky.​ Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7401975 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Stars and The Solar System 16. What are mobile charge carriers in liquid conductors? 1 Mark a. Protons b. Salt c. Neutrons d. Ions Text Solution by our experts ​In liquid conductors, the mobile charge carriers are ions, which move under the influence of an electric field and facilitate the conduction of electricity.​ Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7401970 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Chemical Effects of Electric Current 17. Fluid friction is the friction that occurs in ________________. 1 Mark a. gases only b. liquids only c. both liquids and gases d. vacuum Text Solution by our experts Fluid friction is the friction exerted by fluids on any object moving through them. Fluid friction is observed in both liquids and gases. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7400281 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Friction 18. Wheels reduce friction by ________________. 1 Mark a. increasing surface area in contact b. changing sliding motion to rolling motion to minimise the contact area c. eleminating friction entirely d. increasing the mass of the object Text Solution by our experts Magnitude of friction is greater for larger surfaces in contact. When an object slides, the area of contact is more as compared to an object which is rolling. The wheels change the motion from sliding to rolling and reduce the friction. That’s why it is easier to move objects when on a wheel as compared to when we pull or slide them. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7400286 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Friction 19. Which of these should Aman use as lubricant to reduce friction on chain of his bicycle? 1 Mark a. Talcum powder b. Honey  c. Water d. Grease Text Solution by our experts Answer and Explanation missing. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7401845 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Friction 20. The cracks in the following image show ____________. 1 Mark a. focus b. epicentre c. seismic zones d. tectonic plates Text Solution by our experts Earth’s outermost layer is composed of fragments called tectonic plates. Focus, seismic zone and epicenter are the different points related to the earthquake phenomenon in and around these plates. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7401731 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Some Natural Phenomena 21. Which of the following gland is responsible for the regulation of biological clock in Humans? 1 Mark a. Thymus b. Thyroid c. Parathyroid d. Pineal Text Solution by our experts Pineal Gland is the gland responsible for regulating Sleep-wake cycle in human body. Thyroid gland is responsible for regulating the basal metabolic rate of the person, parathyroid gland helps in maintaining the calcium level in the blood whereas thymus gland is responsible for functioning of lymphocytes. Board: CBSE | Class: VIII | Subject Name: Science | Time to solve: 01:00 min | Question ID: 7321025 | Difficulty Level: Easy | Question Type: Single Choice Question CBSE > VIII > Science > Reaching the Age of Adolescence 22. Handles of cooking utensils are made of _________. 1 Mark a. Melamine b. Bakelite c. Nylon d. PVC  Text Solution by our experts Bakelite is a poor conductor of heat and electricity. Hence, it is used for making electrical switches and utensil handles. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7400806 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Synthetic Fibres and Plastics 23. Choose the INCORRECT pair from the following. 1 Mark a. Natural fibre–Cotton b. Synthetic fibre–Acrylic c. Natural fibre–Polyester d. Synthetic fibre–Rayon Text Solution by our experts Polyester is not a natural fibre but a synthetic fibre. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 01:00 min | Question ID: 7400812 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Synthetic Fibres and Plastics 24. If the area of the wooden block is 51 times of the original area and the force exerted remains the same, then the pressure 1 Mark a. increases. b. remains the same. c. becomes zero. d. decreases. Text Solution by our experts T he f orce acting on a unit area of a surf ace is called pressure. So, the larger the area, smaller the pressure on a surf ace f or the same f orc Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Topic: Pressure | Time to solve: 01:00 min | Question ID: 7216414 | Difficulty Level: Easy | Question Type: Single Choice Question CBSE > VIII > Science > Force and Pressure 25. Isha took half kg refined wheat flour (maida), added some sugar to it and kneaded it with warm water. She added 1 Mark some yeast powder to the flour to make it soft. She left the kneaded flour for two hours and observed that the flour rose in size. What could be the possible reason behind this observation made by Isha? a. Due to the multiplication of yeast in the dough, it rose in size. b. The dough rose due to the production of oxygen gas during respiration by yeast. c. The presence of warm water with sugar caused the dough to increase in size. d. The dough rose due to the production of carbon dioxide gas by yeast. Text Solution by our experts The yeast present in the dough reproduces rapidly and produces carbon dioxide during respiration. Bubbles of the gas fill the dough and increase its volume. Board: CBSE | Class: VIII | Subject Name: Science | Chapter: Chapter | Time to solve: 02:00 min | Question ID: 7285716 | Difficulty Level: Medium | Question Type: Single Choice Question CBSE > VIII > Science > Microorganisms : Friend and Foe Copyright © 2024 Extramarks. All rights reserved.