Sub: Physics Class- XI F.M - 100
Section – A
Choose the correct alternative (MCQ)
Q1. The atmospheric pressure is 106 dyne/cm2. What is its value in SI unit?
a) 10^5newton/m2 (b) 10^6 newton/m2 (c) 10^4newton/m2 (d) 10^3 newton/m2
Q2. Which of the following groups have different dimensions?
a) Potential difference, EMF, voltage (b) Pressure, stress, Youngs modulus (c) Heat, energy, work done (d) Dipole moment, electric flux, electric field
Q3. Which of the following is a dimensional constant?
a) Gravitational constant (b) Dielectric constant (c) Refractive index (d) Relative density
Q4. Two trains of 40 m length are travelling in opposite directions with a velocity of 10 m/s and 15 m/s. What is the time of crossing?
a) 1 s b) 2.4 s c) 3.2 s d) 4.4 s
Q5. A particle is moving with a constant speed along a straight-line path. A force is not required to : a) change its direction b) decrease its speed c) keep it moving with uniform velocity d) Increase its momentum
Q6. Which theorem states that “If a particle under the simultaneous action of three forces is in equilibrium, then each force has a constant ratio with the sine of the angle between the other two forces”? a) Lay’s theorem b) Lami’s Theorem c) Newton’s law d) Faraday’s theorem
Q7. Give an example of motion in two dimensions _________________ a) Motion along a straight line in any direction b) Bird flying c) A flying kite d) Projectile motion
Q8. Circular motion is a _________________ a) Motion in one dimension b) Motion in two dimensions c) Motion in three dimensions d) Motion in four dimensions
Q9. Which is the branch of physics that deals with the motion of a body by considering the cause? a) Statics b) Thermodynamics c) Dynamics d) Astronomy
Q10. When an external force is not applied to the system, its total momentum _____________ a) Becomes zero b) Remains constant c) Increases gradually d) Decreases gradually
Q11. Forces acting for a short duration are called _____________ a) Short force b) Interval force c) Impulsive forces d) Interrupting force
Q12. The inherent property, with which a body resists any change in its state of motion is known as _____________ a) Force b) Momentum c) Inertia d) Acceleration
Q13. Which is the type of collision in which both the linear momentum and the kinetic energy of the system remain conserved? a) Inelastic Collision b) Elastic Collision c) Destructive collision d) None of the options
Q14. State true or false: According to Equivalence of Mass and Energy, it states that mass and energy are NOT interconvertible. a) True b) False
Q15. An electric heater of rating 1000 W is used for 5 hrs per day for 20 days. What is the electrical energy utilized? a) 100 kWh b) 200 kWh c) 120 kWh d) 500 kWh
Q16. Find the potential energy stored in a ball of mass 5 kg placed at a height of 3 m above the ground. a) 121.20 J b) 147.15 J c) 227.31 J d) 182.21 J
Q17. The rotational inertia of a rigid body is referred to as its _________________. a) Moment of energy b) Moment of force c)Moment of inertia d) Moment of acceleration
Q18. If a body is rotating about an axis passing through its centre of mass, the angular momentum of the body is directed along its _________________. a) Circumference b) Radius c) Axis of rotation d) None of the option
Q19 . The combination of rotational motion and the translational motion of a rigid body is known as _________________. a) Frictional motion b) Axis motion c) Angular motion d) Rolling motion
Q20. State true or false: The position of centre of mass does not depend upon the shape, size, and distribution of the mass of the body. a) True b) False
Q21. The sum of kinetic and potential energy is when a missile is launched with a velocity less than the escape velocity. a) 0 b) Negative c) Positive d) None of these options
Q22. What would be the maximum height reached by the body if the body is projected vertically from the surface of the earth of radius R with a velocity equal to half of the escape velocity? a) 2 + R b) R c) R/2 d) R/3
Q23. The satellite having the same time period of revolution as that of the earth is called _________________. a) Stationary satellite b) Geostationary satellite c) Gravitational satellite d) Geo satellite
Q24. State true or false: The gravitational force is a conservative force. a) True b) False
Q25. Which one has higher kinetic energy? Both light and heavy bodies have equal momenta. a)Heavy body b) Light body c) Both d) None of the options
Section – B
Answer the following questions with few words : 2 x 6 = 12
Q26. Why the moment of inertia of a solid disc is smaller than that of a ring of same size and mass?
Q27. Name the process in which (i) momentum is conserved but K.E. is not conserved and (ii) momentum changes but K.E. does not change.
Q28. Two objects having different masses have same momentum. Which one of them will move faster.
Q29. Can an object be at rest as well as in motion at the same time?
Q30. Name Physical Quantities Whose Units are Electron Volt and Pascal.
Q31. What is the shape of the displacement time graph for uniform linear motion?
Section –C
Answer the questions below briefly : 3x 6 = 18
Q32. If Velocity, Time and Force Were Chosen as the Base Quantities, Find the Dimensions of Mass.
Q33. The displacement x of a particle moving in one dimension under the action of the constant force is related to the time by the equation t = x^0.5 -3 where x is in meters and t is in seconds. Find the velocity of the particle at (1) t = 3s (2) t = 6s.
Q34. What is the angle between two forces of 2 N and 3 N having resultant as 4 N?
Q35. Two blocks of masses m1 and m2 are connected by light spring on a smooth horizontal surface. The two masses are pulled apart and then released. Prove that the ratio of their acceleration is inversely proportional to their masses.
Q36. Four particles of mass , 1kg , 2 kg ,3 kg , and 4kg are placed at the four vertices , , and of square of side . Find the position of centre of mass of the system .
Q37. Show That an Artificial Satellite Circling Round the Earth in an Orbit of Radius Obeys Kepler’s Third Law.
Section – D
Directions :
Each of these questions contain two statements, Assertion and Reason. Each of these questions also has four alternative choices, only one of which is the correct answer. You have to select one of the codes (a), (b), (c) and (d) given below.
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion.
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct
Q 38. Assertion : When we change the unit of measurement of a quantity, its numerical value changes.
Reason : Smaller the unit of measurement smaller is its numerical value.
Q39. Assertion : Displacement of a body may be zero when distance travelled by it is not zero.
Reason : The displacement is the longest distance between initial and final position.
Q40. Assertion : On a rainy day, it is difficult to drive a car or bus at high speed.
Reason : The value of coefficient of friction is lowered due to wetting of the surface.
Q41. Assertion : A man rowing a boat upstream is at rest with respect to the bank. He is doing no external work.
Reason : Work done by constant force, W = F s cosθ.
Q42. Assertion : A body becomes massless at the centre of earth.
Reason : This follows from g’ = g (1 – d/R)
Section – E
Q43. Read the passage below and answer the questions that follow ; 1 x 5 =5
Conservation of Momentum
This principle is a consequence of Newton’s second and third laws of motion.
In an isolated system (i.e., a system having no external force), mutual forces (called internal forces) between pairs of particles in the system causes momentum change in individual particles.
Let a bomb be at rest, then its momentum will be zero. If the bomb explodes into two equal parts, then the parts fly off in exactly opposite directions with same speed, so that the total momentum is still zero. Here, no external force is applied on the system of particles (bomb).
(i) A shell of mass 10 kg is moving with a velocity of 10 ms-1 when it blasts and forms two parts of mass 9 kg and 1 kg respectively. If the first mass is stationary, the velocity of the second is (a) 1 m/s (b) 10 m/s (c) 100 m/s (d) 1000 m/s 1
(ii) A bullet of mass 10 g is fired from a gun of mass 1 kg with recoil velocity of gun 5 m/s. The muzzle velocity will be (a) 30 km/min (b) 60 km/min (c) 30 m/s (d) 500 m/s 1
(iii) A bullet of mass 0.1 kg is fired with a speed of 100 m/s. The mass of gun being 50 kg, then the velocity of recoil becomes (a) 0.05 m/s (b) 0.5 m/s (c) 0.1 m/s (d) 0.2 m/s 1
(iv) Two masses of M and 4M are moving with equal kinetic energy. The ratio of their linear momenta is (a) 1:8 (b) 1:4 (c) 1:2 (d) 4:1 2
Answer the following questios : 5 x7 = 35
Q44. A physical quantity P is related to four observables a, b,c and d and as follows: P = a^3b^2 /(c^.5 d^.5) The percentage errors of measurement in a , b, c and d are 1 and 2 respectively. What is the percentage error in the quantity P? If the value of P calculated using the above relation turns out to be 3.763, to what value should you round off the result?
Q45 . A particle is moving along a straight line and its position is given by the relation x = (t^3 – 6t^2 –15 t + 40 ) m
Find
a) The time at which velocity is zero.
b) Position and displacement of the particle at that point.
c) Acceleration
Q46. A man can swim with a speed of 4km/ h in still water. How long does he take to cross a river wide if the river flows steadily at 3km/h and he makes his strokes normal to the river current? How far down the river does he go when he reaches the other bank?
Q47. A monkey of mass 4 kg climbs on a rope which can stand a maximum tension 600 N. In which of the following cases will the rope break? The monkey (a) climbs up with an acceleration of 6m/s^2 (b) climbs down with an acceleration of 4m/s^2 (c) climbs up with a uniform seed of 5 ms (d) falls down the rope freely under gravity. Take g = 10m/s^2 and ignore the mass of the rope.
Q48. The resistance of certain platinum resistance thermometer is found to be 2.56 ohm at 0 degree celsius and 3.56 ohm at 1000 degree celsius . When the thermometer is immersed in a given liquid, its resistance is observed to 5.06 ohm . Determine the temperature of liquid?
Q49. A rope of negligible mass is wound round a hollow cylinder of mass 3 kg and radius 40 cm. What is the angular acceleration of the cylinder if the rope is pulled with a force of 30 N ? What is the linear acceleration of the rope? Assume that there is no slipping.
Q50 . A 400 kg satellite in a circular orbit of radius 2 Re about the earth. Calculate the kinetic energy, potential energy and total energy of the satellite. ( Re = 6.4 x 10 ^6 m M = 6x 10^24 kg
কোন মন্তব্য নেই:
একটি মন্তব্য পোস্ট করুন