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

Under Graduate Entrance Exams NEET Entrance Exam # Physics Laws of Motion Prepare / Learn

Q1. A pebble of mass 0.05 kg is thrown vertically upwards. Give the direction and magnitude of the net force on the pebble, during its upward motion, Ignore air resistance

A. 0

B. 0.05 N vertically down

C. 0.5 N vertically down

D. 0.5 N vertically up

Answer : Option C
Explaination / Solution:

F = mg = 0.05 x 10 = 0.5 N

Under Graduate Entrance Exams NEET Entrance Exam # Physics Physical World Prepare / Learn

Q2. Universal law of gravitation does not explain

A. motion of planets around the sun

B. pendulums

C. origin of gravitational attraction

D. bodies falling towards the earth

Answer : Option C
Explaination / Solution:

Universal law of Gravitational explain the force of attraction between two bodies having mass and placed at a distance but it never explain how this force generated and what is the origin of this.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Electrostatic Potential and Capacitance Prepare / Learn

Q3. For a parallel plate capacitor ______________ possible potential difference between the capacitor plates

A. dielectric increases the maximum

B. dielectric decreases the maximum

C. dielectric decreases the minimum

D. dielectric increases the minimum

Answer : Option B
Explaination / Solution:

When a dielectric is introduced between two charged plates of a capacitor having a charge Q and maintained at a potential difference of V, a reverse electric field is set up inside the dielectric due to dielectric polarization.

This reduces the electric field in between the plates. The potential is also reduced. Maximum potential is dependent on the charge on the plates. As the charge remains constant, the presence of the dielectric decreases the maximum potential between the plates.

Under Graduate Entrance Exams NEET Entrance Exam # Physics System of Particles and Rotational Motion Prepare / Learn

Q4. A child swinging on a swing in a sitting position stands up. Then, the time period of the swing will

A. Increase if the child is tall and decrease if the child is short.

B. Increase

C. Decrease

D. Remains the same

Answer : Option C
Explaination / Solution:

As the child stand up then Centre of mass is shifted in upwards direction from the sitting position of child, thus decreasing the effective length of the swing, so as the time period is proportion to square root of length, thus time period decreases.

time period

$\begin{aligned} T = 2 π \sqrt{\frac{l}{g}} \\ T \propto \sqrt{l} \end{aligned}$

Time period of swing decreases as effective length decreases.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Mechanical Properties of Fluids Prepare / Learn

Q5. If

ρ

is the density of the fluid flowing with a speed v, D stands for the dimension of the pipe, and

η

is the viscosity of the fluid Reynolds number

R_{e}

is given by

R_{e} =

\frac{ρ v D}{η}

R_{e} =

\frac{ρ D}{η}

C. Re=ρvDη

R_{e}

\frac{ρ v}{η}

Answer : Option A
Explaination / Solution:

It is a dimension less number comprised of the physical characteristics of the flow. An increasing Reynolds number indicates an increasing turbulence of flow.

It is defined as: $R_{e} =$ $\frac{ρ v D}{η}$

where;
v is the flow velocity
D is a characteristic linear dimension
ρ fluid density(kg/m3)
$η$ is dynamic viscosity (Pa.s)
ν kinematic viscosity (m2/s), $v =$ $\frac{η}{ρ}$

Under Graduate Entrance Exams NEET Entrance Exam # Physics Kinetic Theory Prepare / Learn

Q6. Figure shows plot of PV/T versus P for 1.00

\times

1 0^{- 3}

kg of oxygen gas at two different temperatures The dotted plot corresponds to

A. ‘super heated’ gas behavior

B. ‘real’ gas behavior

C. ‘super cooled’ gas behavior

D. ‘ideal’ gas behavior

Answer : Option D
Explaination / Solution:

for 1 mole of ideal gas, according to ideal gas equation

$\begin{aligned} P V = R T \\ \frac{P V}{T} = R = c o n s t . \end{aligned}$

hence graph must be with zero slope. So that dotted line show ‘ideal’ gas behavior and curved line shows deviation from ‘ideal’ gas behavior

Under Graduate Entrance Exams NEET Entrance Exam # Physics Ray Optics and Optical Instruments Prepare / Learn

Q7. Farsighted or hypermetropic eye can be corrected by

A. Plano-concave lens

B. cylindrical lens

C. diverging lens

D. converging (positive) lens

Answer : Option D
Explaination / Solution:
No Explaination.

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

Q8. β -rays and γ -rays are respectively

A. neutrons and electromagnetic radiation of wavelengths shorter than X-rays

B. electrons and electromagnetic radiation of wavelengths shorter than X-rays

C. protons and neutrons of wavelengths shorter than X-rays

D. protons and electromagnetic radiation of wavelengths shorter than X-rays

Answer : Option B
Explaination / Solution:
No Explaination.

Under Graduate Entrance Exams NEET Entrance Exam # Physics Alternating Current Prepare / Learn

Q9. 25.0 μF capacitor is connected to a 220 V, 50 Hz source. Capacitive reactance and the current (rms) in the capacitor are circuit

A. 102 Ω , 1.03 A

B. 127 Ω, 1.73 A

C. 111 Ω , 1.73 A

D. 127 Ω , 1.23 A

Answer : Option B
Explaination / Solution:

$\begin{aligned} C = 25 μ F \\ V = 220 v o l t \\ f = 50 H z \end{aligned}$

Capacitive reactance

$\begin{aligned} X_{C} = \frac{1}{ω C} = \frac{1}{2 π f C} = \frac{1}{2 \times 3.14 \times 50 \times 25 \times 10^{- 6}} \\ X_{C} = 127 Ω \end{aligned}$

rms current

$i = \frac{V}{X_{C}} = \frac{220}{127} = 1.73 A$

Under Graduate Entrance Exams NEET Entrance Exam # Physics Thermal Properties of Matter Prepare / Learn

Q10. In which mode of heat transfer is there material movement?

A. radiation

B. none of the three

C. conduction

D. convection

Answer : Option D
Explaination / Solution:

Convection is the heat transfer due to bulk movement of molecules within fluids.

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