Fill in the blanks : Chapter:Habitat
(i)In the sea plants and animal surrounded by -------------------------(saline water) (ii) The place where living beings live is called their -------------(Habitat) (iii) In Cactus plant, ---------------are reduced to spines (Leaves) (iv) Global warming increases the concentration of ------in the atmosphere(carbon dioxide) (v) ------------are examples for Decomposers (Bacteria and fungus) (vi) Living component of a habitat is called as -------------- (Biotic) (vii) Anything which produce and response in an organism is called as -----------(Stimulus) (viii) A potted plant is kept in a card board box with a small slit of sun light exhibits ----- Movement (Phototrophic) (25 questions total)
 CBSE MCQ’s TEST PAPER -1
CLASS - X Science: Magnetic Effects of Currents 1. When a bar magnet is broken into two pieces: (A) we will have a single pole on each piece (B) each piece will have two unlike poles (C) each piece will have two like poles (D) None of these 2. The magnetic field intensity produced due to a current carrying coil is maximum at : (A) any point (B) the centre of the coil (C) any point lying on the axis of the coil (D) points lying between centre of the coil and its circumference 3. The direction of magnetic lines of force produced by passing a direct current in a conductor is : (A) Perpendicular to the conductor & coming outwards (B) parallel to conductor (C) Surrounding the conductor and of circular nature (D) perpendicular to the conductor & coming inwards 4. Which of the following statement is not correct about two parallel conductors carrying equal currents in the same direction ? (A) Each of the conductors will experience a force. (B) The two conductors will repel each other. (C) There are concentric lines of force around each conductor. (D) Each of the conductors will move if not prevented from doing so. 5. Which of the following determine the direction of magnetic field due to a current carrying conductor ? (A) Faraday’s laws of electromagnetic induction. (B) Fleming’s left-hand rule. (C) Lenz’s law. (D) Maxwell’s cork screw rule. 6. A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then : (A) a current will be induced in the coil (B) no current will be induced in the coil. (C) only emf will be induced in the coil (D) am emf and current both will be induced in the coil X Magnetic Effects of Currents MCQ'S - I (10Q) Download File X Magnetic Effects of Currents MCQ'S - 2 (10Q) Download File X Magnetic Effects of Currents Notes Visit....... X Magnetic Effects of Currents CBSE Test Paper - 1 Download File X Magnetic Effects of Currents CBSE Test Paper - 2 Download File  1. An athlete runs a certain rest before taking a long jump. Why?
An athlete runs a certain distance to accelerate himself and gain enough momentum so that he can jump through the maximum possible length. 2. Springs are provided in car seats. Why? The springs in the car seats absorb shock (sudden jumps) due to the roughness of the road. Thus, making the ride more comfortable. 3. A gun of mass 1500 kg fires a shell of mass 15kg with velocity 150 m/s. calculate velocity of recoil of the gun. Before firing, total momentum of the gun and shell is = 0 (they were all at rest) After firing, the momentum of the shell = 15 X 150 = 2250 Ns The momentum of the gun is = 1500v Ns By conservation of momentum, Total momentum before firing = Total momentum after firing => 0 = 2250 + 1500v => v = -2250/1500 = -1.5 m/s The negative sign implies the recoil velocity of the gun is opposite to the velocity of the shell. 4. Why cricketer pulls his hands backwards while catching the ball Ans: cricketer pulls his hands backwards while catching the ball. When he does so, momentum of the ball reduces slowly, and time t required for this increases. As per F =DP/t , as t increase, magnitude of F decreases. As a result cricketer can catch the ball, easily, without any injury. 5. Why A karate player in order to break a brick, hits it quickly. Ans: A karate player in order to break a brick, hitsit quickly, so in a short time there is a large change in momentum and as per F =change in p/t as large force acts on the brick and it breaks. 6. What is impulse of Force? Ans: Product of force and the time period for which force is acting is called impulse of force. If, on an object, Force F acts for time t. Then Impulse of force = force x time I = F x t= change in p Like force, impulse of force is also a vector quantity. Direction of impulse of force is same as the direction of force. Unit of impulse of force is kg m/s or Ns. For more Question click Here  HOTS QUESTIONS
1. In one of the industrial process used for manufacture of sodium hydroxide, a gas ‘X’ is formed as by – product. The gas ‘X’ reacts with lime water to give a compound ‘Y’ which is used as a bleaching agent in chemical industry. Identify ‘X’ and ‘Y’ giving the chemical equation of the reaction. Ans: In the manufacture of sodium hydroxide, hydrogen gas and chlorine gas (X) are formed as by products. When chlorine gas (X) reacts with lime water, it forms calcium oxy chloride (bleaching powder) Y. 2NaCl (aq) + 2 H2O (L)----> 2NaOH (Aq) + Cl2 (G) + H2 (G) ‘X’ Þ Cl2 gas Ca(OH)2 + Cl2----> CaOCl2 + H2O Q. Dry hydrogen chloride gas does not turn blue litmus, whereas hydrochloric acid does. Why? Ans: In the dry state, hydrogen chloride (HCl) does not release H+ ions. Therefore, it cannot behave as an acid. When dissolved in water, it forms hydrochloric acid. It dissociates to give H+ ions in solution and behaves as an acid. Acid when react with metals release hydrogen gas but there is one acid which when reacts with metals does not release hydrogen except for two metals. Prove this statement. Acid + Metal ----> Salt + Hydrogen e.g. 2HCl + 2Na ---->2NaCl + H2 H2SO4 + 2Na ----> Na2SO4 + H2 HNO3 + Na ---->No hydrogen gas. Because nitric acid is strong oxidising agent. Nitric acid reacts only with Mg and Mn to give hydrogen gas. Mg + 2HNO3 ----> Mg(NO3)2 + H2 Mn + 2HNO3---->Mn(NO3)2 + H2 Self Practice Q. 4 Name the properties responsible for the following uses of baling powder. (i) Baking industry (ii) As an antacid (ii) As soda-acid fire extinguisher. Q. 5 What is meant by water of crystallisation of a substance? What is its importance? Q. 6 What effect does an increase in concentration of ‘H’ ions in a solution have on the pH of a solution Q. 7 Fresh milk has a pH Of 6. When it changes to curd, will its pH value increase or decrease? Why? Q. 8 How does the flow of acid rain water into a river make the survival of aquatic life in a river difficult? Q. 9 Arrange in the increasing order of their pH values: NaOH solution, Blood, Lemon juice, Q. 10 Two solutions A and B have pH values of 5 and 8 respectively. Which solution will be basic in nature? For more stuff visit ......  1. An object of mass 2 kg is sliding with a constant velocity of 4 m/ s on a frictionless horizontal table. The force required to keep the object moving with the same velocity is
(a) 32 N (b) 0 N (c) 2 N (d) 8 N (b] 2. Rocket works on the principle of conservation of (a) mass (b) energy (c) momentum (d) velocity [c] 3. A car is moving at 45 km/hr.A constant force acts on the car for 10 sc .So that it's velocity becomes 63 km/hr .The distance travelled by car during this interval of 10 sec is : a) 100 m b) 150 m c) 200 m d) 50 m [b] What is the definition of balanced and unbalanced force? When two equal forces acting on an object in opposite directions called balanced force. When something does not move the forces are balanced, e.g. Gravity pulls a table down but that table is pushed up by the floor or the ground it stands on so doesn’t’ move. An Unbalanced force is needed for something to change movement or change direction, e.g. aseesaw moving up and down because the forces are not equal. Net force: - The sum of all the forces acting on a body is known as net force. Difference between Balanced force and unbalanced force. Balanced force:- If net force on a body is zero it is called balanced force. Balanced forces do not cause a change in motion. They are equal in magnitude and opposite in direction. Therefore, the resultant of these forces will be zero. Example: Two persons pushing a box with the same force in opposite directions. Unbalanced forces:- If net force on a body is non-zero it is called unbalanced force. Forces whose resultant is not equal to zero are called unbalanced forces. For example: An arm wrestling competition among a strong person and a weak one. The resultant force will be in the direction of the force applied by the strong person. What Is Inertia By Newton's law we know that ,a body at rest will remain at rest and a body in motion will continue in a straight line unless it is compelled by an external force.This tendency of a body is called inertia.So we can say that 'Inertia is that property of a body due to which it resists a change in its state of rest or of uniform motion.' When the brakes are applied to the bike the back seater moves forward why? Read more » you may also like IX Force and laws of motion solved questions: NCERT / CBSE Textbook Exercise Questions Solved For full study package free visit |
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