Physics MCQs
Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, NDA, CDS and all one day examinations of India. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. Which among the following lens is used to correct Presbyopia?
[A] Convex
[B] Concave
[C] Bifocal
[D] Cylindracal
Show Answer
Correct Answer: C [Bifocal]
Notes:
In Presbyopia defect both near and far object are not clearly visible i.e., far point is lesser than infinity and near point greater than 25 cm. This can be removed either by using two separate spectacles one for myopia and other for hypermetropia or by using bifocal lens. It is an old age disease. At old age ciliary muscles lose their elasticity so they can not change the focal length of eye lens effectively and eye losses its power of accommodation
2. The value of acceleration due to gravity is __________?
[A] Minimum at equator and maximum at poles
[B] maximum at equator and minimum at poles
[C] equal at poles and equator
[D] None of the above
Show Answer
Correct Answer: A [Minimum at equator and maximum at poles]
Notes:
The value of acceleration due to gravity is maximum at equator. This is because the distance from the center is minimum at the equator.
3. Which of the following causes the drop of water to be in spherical shape?
[A] Viscosity
[B] Air resistance
[C] Surface tension
[D] Temperature
Show Answer
Correct Answer: C [Surface tension]
Notes:
Surface tension is the tendency of liquid surfaces to shrink into the minimum surface area possible. Surface tension allows insects, usually denser than water, to float and slide on a water surface. It is the reason for the water droplet’s round shape.
4. Laterite soils’ are formed due which of the following actions?
[A] Leaching
[B] Erosion
[C] Deposition of fertile riverine silt
[D] Mechanical Weathering of Igneous Rocks
Show Answer
Correct Answer: A [Leaching]
Notes:
Laterite soils are formed through a process known as leaching, which occurs in tropical and subtropical regions where there is a high amount of rainfall and intense weathering of rocks. In this process, rainwater percolates through the soil, dissolving and removing the soluble nutrients and minerals. Over time, this causes the formation of a hard, clay-like soil layer that is rich in iron and aluminum oxides. This soil is typically reddish in color due to the presence of these oxides. Laterite soils are not very fertile and are generally used for grazing or for growing crops that are adapted to low-nutrient environments, such as cassava and rubber.
5. When you throw a ball with an angle to the horizontal (projectile); the ball has __:
[A] Uniform velocity in horizontal direction but uniform acceleration in vertical direction
[B] Uniform acceleration in horizontal direction but uniform velocity in vertical direction
[C] Uniform acceleration in both horizontal and vertical directions
[D] Uniform velocity in both horizontal and vertical directions
Show Answer
Correct Answer: A [ Uniform velocity in horizontal direction but uniform acceleration in vertical direction]
Notes:
The motion of a projectile is two dimensional motion consisting of (i) horizontal motion and (ii) vertical motion. Hence, at any instant, the velocity of a projectile has two components (i) horizontal component and (ii) vertical component. The horizontal component remains unchanged throughout the flight as there is no acceleration in horizontal direction. The vertical component is continuously affected by the force of gravity. Thus, the horizontal motion is uniform motion but the vertical motion is uniformly accelerated motion.)
6. Due to which of the following phenomena, the coloured glass appears white when crushed into fine powder?
[A] Total Internal Reflection
[B] Diffraction
[C] Scattering
[D] Refraction
Show Answer
Correct Answer: C [ Scattering]
Notes:
When the glass is crushed into fine powder the light incident is totally scattered without the absorption so due to the composite light crushed glass appears white.
7. Which of the following is correct about the properties of Gravitational Forces?
[A] They are the strongest forces in nature
[B] They observe inverse square law
[C] Both a and b
[D] None
Show Answer
Correct Answer: B [They observe inverse square law]
Notes:
Gravitational Forces are the weakest forces in nature. They obey inverse square law as they vary inversely as the square of the distance between the two bodies. They are central forces and conservative forces. They operate over very long distances having an infinite range.
8. Which of the following conditions is true for two vectors to be collinear?
[A] Equal magnitude
[B] Same Direction
[C] Acting along the parallel straight lines
[D] Both a and c
Show Answer
Correct Answer: C [Acting along the parallel straight lines]
Notes:
Two vectors are said to be collinear if they are acting along the parallel straight lines. The collinear vectors may or may not have equal magnitude.
9. What is the angular acceleration of a body moving with constant angular velocity?
[A] equal to the angular velocity
[B] 1
[C] 0
[D] Can’t be determined
Show Answer
Correct Answer: C [0]
Notes:
The angular acceleration of a body moving with constant angular velocity is 0. Angular acceleration of an object in circular motion is defined as the time rate of change of its angular velocity.
10. What is the SI unit of acceleration due to gravity?
[A] ms-2
[B] ms-3
[C] Kgms-2
[D] ms-1
Show Answer
Correct Answer: A [ms-2]
Notes:
The acceleration due to gravity is the acceleration set up in the body when it falls freely under the effect of gravity alone. The SI unit of acceleration due to gravity is ms-2
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