JEXPO 2013: Physics Question PART(1-25 Q)

1. When a person uses a convex lens as a simple magnifying glass the object must be placed at a distance.
• Less than the focal length
• More than the focal length
• Less than twice the focal length
• More than twice the focal length
2. The end product of radioactive decays is.
• carbon
• helium
• hydrogen
3. When a vapor condenses into liquid.
• It absorbs heat
• It rejects heat
• Its temperature rises
• Its temperature falls

4. One surface of a lens is convex and the other is concave. If radii of curvature are r1 and r2 respectively, then the lens will be convex if  :

5. An object is placed at a distance of f/2 from a convex lens of focal length f. The image will be:
• At one of the foci, virtual and double of its size
• Greater than 1.5 but less than two times
• At 2f, virtual and erect
• None of these

6. A motorcycle and a car moving on a horizontal Road with the same velocity. If they are brought to rest by application of brakes, provided equal retardation then:
• The motorcycle will stop at a certain distance
• The car will stop at a shorter distance
• Both will stop at the same time
• Nothing can be predicted

7. Choose the Correct sequence of substances which are ordered in an increasing order of forces of attraction between the particles:
• Water, oxygen, sugar,
• Sugar, water, oxygen
• Sugar, oxygen, water
• Oxygen, water, sugar

8. In a Tsunami, the entire ocean, from the surface to the bottom, participate in the wave motion. For such waves, the wave speed is given by v = √gh where g is the acceleration due to gravity and h=3.5 km, is the depth of the ocean surface. A Tsunami has been detected at a point 250 km from the shore. How much time would it take to reach the shore?
• 2.5 hours
• 1 hour
• 25 minutes
• 6 minutes

9. A thin wire of resistance 4Ω (4 Ohm) is bent to form a circle. The resistance across any diameter is :

10. The note middle C played on the piano differs from middle C played on the violin because of a difference in :
• Frequency
• Wavelength
• Fundamentals
• Harmonics

11. A batch of five resistors has the same value. The Ratio of the maximum and the minimum resistance that can be made out of them is :
• 05:01
• 10:04
• 02:01
• 25:01

12. Which device would most likely be classified as a load in an electrical circuit :
• Battery
• Lightbulb
• Ammeter
• Switch

13. If the wavelength if the sound wave increases, the pitch of the sound :
• Decreases
• Increases
• Remain unchanged
• None of these

14. A metallic wire of a specific resistance 's' is stretched in such a way that its length is doubled and area of cross section is halved. Then the specific resistance of the wire will be :
• 2s
• s/ 2
• s
• s/4

15. If a glass prism is placed inside water then is dispersive power :
• Remain unchanged
• Decreases
• Increases
• May increase or decrease depending on the dispersive angle of the prism

16. In the case of vibration, the restoring force is :
• Proportional to displacement
• Proportional to velocity
• Proportional to kinetic energy
• Proportional to potential energy

17. A current is passed through a conducting spring. Then this spring :
• Get compressed
• Gets expanded
• Oscillates
• Remain unchanged

18. The ratio of masses of two bodies P and Q is 1:8 and the ratio of the kinetic energies is 2:1, then the ratio of their Momentums is :
• 1:4
• 1:2
• 4:1
• 1:16
19. A spacecraft of mass M moving with velocity v in space explodes and breaks into two pieces. After the explosion, a mass m of the spacecraft is left stationary. The velocity of the other part is :

• mv/M-m
• Mv/(M-m)
• (M+m)/M
• Mv/m
20. The resultant of two vectors of magnitudes 3 unit and 4 unit is 5 unit. The angle between the two vectors is :

• 𝝅/2
• 𝝅/4
• 𝝅
• 3𝝅/4
21. If the weight of a body is 9.8 kg then the mass of the body is :

• 980 gm
• 1 kg
• 9.8 kg
• 1 gm
22. The dimension of specific gravity is :

• M0L0T0
• ML-1T-2
• ML-3T-0
• MLT-2
23. A body of mass 10kg is falling vertically with uniform velocity. What is the resisting force of air?
• 0
• 5kg-wt
• 10kg-wt
• 15kg-wt
24. If the electronic charge is 1.6 x 10-19 C, then the number of electrons passing through a section of wire per second, when the wire carries a current 2A, is :
• 1.25x1017
• 1.6 x 1017
• 1.25 x 1019
• 1.6 x 1019
25. The kinetic energy of a body of mass m is E. The momentum of the body is

• mE
• 2mE
• 2mE
• 2√mE

NEXT PART(25-50 Q)

Source: Oriental MCQ (2018)
Author: Abhinandan Singh