Physics | NEET Entrance Exam | Under Graduate Entrance Exams Online Objective Test

Under Graduate Entrance Exams NEET Entrance Exam # Physics Moving Charges and Magnetism Prepare / Learn

Q1. A proton (charge + e coul) enters a magnetic field of strength B (Tesla) with speed v, parallel to the direction of magnetic lines of force. The force on the proton is

A. zero

B. evB/2

C. evB

D. α

Answer : Option A
Explaination / Solution:

Lorentz force is given by

F = B q v \sin θ

When the proton enters the magnetic field parallel to the direction of the lines of force,

θ = 0

.Therefore F = 0

Under Graduate Entrance Exams NEET Entrance Exam # Physics Electronic Devices Prepare / Learn

Q2. Transistor was invented by

A. Lee de Forest

B. Marconi

C. Shockley

D. Fleming

Answer : Option C
Explaination / Solution:

A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley. The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Motion in A Straight Line Prepare / Learn

Q3.

A truck has a velocity of 2 m /s at time t=0. It accelerates at 2 m / $s^{2}$ on seeing police .What is its velocity in m/s at a time of 2 sec

A. 3

B. 7

C. 6

D. 4

Answer : Option C
Explaination / Solution:

Initial velocity u = 2 m/s

final velocity = v m/s

Time duration = final time - initial time = 2-0 = 2 s

acceleration a = 2 m/s2

We know,

v = u + at

=> v = $2 + 2 \times 2$

=> v = 6 m/s

Under Graduate Entrance Exams NEET Entrance Exam # Physics Waves Prepare / Learn

Q4. A stretched string fixed at both ends has n nodes then the length of string in terms of wavelength is

\frac{λ}{2}

\frac{λ}{2}

B. (n - 1)

\frac{λ}{2}

C. (n + 1)

\frac{λ}{2}

D. (2n - 1)

\frac{λ}{2}

Answer : Option B
Explaination / Solution:
No Explaination.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Electromagnetic Induction Prepare / Learn

Q5. Two ends of a horizontal conducting rod of length l are joined to a voltmeter. The whole arrangement moves with a horizontal velocity v, the direction of motion being perpendicular to the rod. Vertical component of the earth's magnetic field is B. The voltmeter reads

A. Blv only if the rod moves westward

B. Blv only if the rod moves eastward

C. zero .

D. Blv if the rod moves in any direction

Answer : Option C
Explaination / Solution:

Induced EMF is zero because flux linked with it remains constant.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Electromagnetic Waves Prepare / Learn

Q6. Part of the electromagnetic spectrum to which 2.7 K [temperature associated with the isotropic radiation filling all space-thought to be a relic of the ‘big-bang’ origin of the Universe] belongs is

A. Microwave

B. Ultraviolet

C. Radio (short wavelength end

D. gamma rays

Answer : Option A
Explaination / Solution:
No Explaination.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Dual Nature of Radiation and Matter Prepare / Learn

Q7. If work function of a metal surface is 3.45 eV ,then maximum wavelength of a photon required to eject a photoelectron is

A. 3.6

\times 1 0^{- 7}

B. 4.0

\times 1 0^{- 7}

C. 3.6

\times 1 0^{- 7}

D. 3.4

\times 1 0^{- 7}

Answer : Option A
Explaination / Solution:
No Explaination.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Communication Systems Prepare / Learn

Q8. need for modulation arises from antenna considerations. If base band signal is to be transmitted then

A. size of antenna would be huge

B. none of these

C. size of antenna would be very small

D. shape of antenna would be complex

Answer : Option A
Explaination / Solution:
No Explaination.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Motion in A Plane Prepare / Learn

Q9.

A sports car has a “lateral acceleration” of 0.96g = 9.4 m $s^{- 2}$ . This is the maximum centripetal acceleration the car can sustain without skidding out of a curved path. If the car is traveling at a constant 40 m/s on level ground, what is the radius R of the tightest unbanked curve it can negotiate?

A. minimum radius = 180 m

B. minimum radius = 160 m

C. minimum radius = 170 m

D. minimum radius = 175 m

Answer : Option C
Explaination / Solution:

The car is in uniform circular motion because it’s moving at a constant speed along a curve that is a segment of a circle. Hence we know

R= $\frac{v^{2}}{a_{r a d}}$ = $\frac{(40)^{2}}{9.4}$ =170 m

This is the minimum turning radius because arad is the maximum centripetal acceleration.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Electric Charges and Fields Prepare / Learn

Q10. A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of

8 0.0 μ C / m^{2}

. (a) Find the charge on the sphere. (b) What is the total electric flux leaving the surface of the sphere?

A. 1.55×10−3C,1.6×108Nm2/C

B. 1.25×10−3C,1.2×108Nm2/C

C. 1.35×10−3C,1.6×108Nm2/C

D. 1.45×10−3C,1.6×108Nm2/C

Answer : Option D
Explaination / Solution:

Physics - Online Test

Physics | Online Objective Test | Start Test

Prepare Before Start Test | Learn

UPSC Civil services Entrance exams | Online Test

GATE Exam | Online Test

Under Graduate Entrance Exams | Online Test

Problem Solving and Reasoning | Online Test

CAT Entrance Exams | Online Test

CLAT LAW Entrance exams | Online Test

Banking Entrance exams | Online Test

UGC NET Entrance exams | Online Test

TANCET Anna University | Online Test

TN State Board | Online Test