JUPEB 2015: PHYSICS – SCI-J155 – Multiple Choice Questions

A particle with rest mass m moves with speed 0.6c. Its kinetic energy is _________

Which of the following particles is stable?

To travel at a constant speed, a car engine provides 24 KW of useful power. The driving force on the car is 600 N. At what speed does it travel?

A pure semiconductor at room temperature has:

The proper time between two events is measured by clocks at rest in a reference frame in which the two events

A handbag weighing 162 N is carried by two students each holding the handle of the bag next to him. If each handle is inclined at 60^o to the vertical, find the force on each student’s arm.

A rope is being used to pull a mass of 10 kg vertically upward. Determine the tension on the rope, if starting from rest, the mass acquires a velocity of 4 ms^-1 in 8s [g= 10ms^-2].

A boy observes a piece of stone at the bottom of a river 6.0 m deep. If he looks vertically from the surface of the river, how far does the stone appear to be from him?

$\left[\mathrm{Refractive} \mathrm{index} \mathrm{of} \mathrm{water} = \frac{4}{3}\right]$

A cell has an internal resistance of 0.01 Ω. An instrument that can measure the resistance accurately is _________

A conductor of length 2m carries a current of 0.8A while kept in a magnetic field of magnetic flux density 0.5 T. The maximum force acting on it is

The bond that forms a semiconductor is

The particle nature of light is demonstrated by

______ law states that at constant pressure, the volume of a given mass of gas is directly proportional to the absolute temperature.

Use dimensional analysis to determine which of the following equations is certainly wrong:

$$\begin{gathered} \mathrm{I}. \mathrm{\lambda } = \mathrm{vt} \\ \mathrm{II}. \mathrm{F}=\frac{\mathrm{m}}{\mathrm{a}} \\ \mathrm{III}. \mathrm{F}=\frac{\mathrm{mv}}{\mathrm{t}} \\ \mathrm{IV}. \mathrm{h}=\frac{{\mathrm{v}}^2}{2\mathrm{g}} \\ \mathrm{V}. \mathrm{v}=\left(2\mathrm{gh}\right)\frac{1}{2} \end{gathered}$$

A _________ can hear sound as high as 100,000Hz

For an electron to be ejected from the surface of a metal, the radiation energy must be ___________

________ is the only natural satellite of the earth

A 2-kilogram block rests at the edge of a platform that is 10 meters above level ground. The block is launched horizontally from the edge of the platform with an initial speed of 3 meters per second. Air resistance is negligible. The time it will take for the block to reach the ground is approximately _______

$\left[\mathrm{Take} \mathrm{g}=10\raisebox{1ex}{$\mathrm{m}$}\!\left/ \!\raisebox{-1ex}{${\mathrm{s}}^2$}\right.\right]$

A diver initially moving horizontally with speed v dives off the edge of a vertical cliff and lands in the water a distance d from the base of the cliff. How far from the base of the cliff would the diver have landed if the diver initially had been moving horizontally with speed 2 v?

A truck traveled 400 meters north in 80 seconds, and then it traveled 300 meters east in 70 seconds. The magnitude of the average velocity of the truck was most nearly

The field intensity at a point close to a charged plane conductor situated in air is 3.5 × 10⁶ Vm^-1. The surface density of charge is: [Take the permittivity of free space as 8.85 ×10−¹² F/m]

Two parallel horizontal metal plates are 25 mm apart and a potential difference of 1000 V is applied across the plates. The field intensity between the plates is:

Which of the following defines the Heisenberg uncertainty principle for position and momentum?

The ejection of an alpha particle from a nucleus results in

Hydrogen-3 is a radioactive isotope of hydrogen. Which type of radiation would you expect an atom of this isotope to emit?

(i) beta particle

(ii) an alpha particle

(iii) a gamma-ray

Which of the following are derived units?

(i) Metres

(ii) Coulomb

(iii) Kilogram

(iv) Ampere

(v) Joule

The dimension of power is _________

Which of the following quantities has the same unit as kilowatt-hour?

An elastic string of length 20cm extends to 24cm when it supports a weight of 50N. The energy stored in the string is?

Which of the following radiations will pass through a sheet of paper?

(I) Alpha rays

(II) Beta rays

(III) Gamma rays

A metal having a work function of 5.76eV is illuminated with a radiation of 7.88eV. The kinetic energy of the electrons emitted from the metal surface is

What is the energy associated with an X-ray of wavelength 9×10^-10m (Planck’s constant = 6.6×10^-34Js and velocity of light 3×10⁸m/s).

Two football players with masses 75 kg and 100 kg run directly toward each other with speeds of 6 m/s and 8 m/s respectively. If they grab each other as they collide, the combined speed of the two players just after the collision would be:

$$\begin{gathered} \mathrm{The} \mathrm{velocity} \mathrm{of} \mathrm{sound} \mathrm{in} \mathrm{a} \mathrm{gas} \mathrm{is} \mathrm{given} \mathrm{by} {\mathrm{v}}_2=\sqrt{\frac{\mathrm{\gamma P}}{\mathrm{p}}} \\ \mathrm{where} \mathrm{the} \mathrm{symbols} \mathrm{have} \mathrm{their} \mathrm{usual} \mathrm{meanings}. \mathrm{For} \mathrm{a} \\ \mathrm{particular} \mathrm{gas} \mathrm{under} \mathrm{certain} \mathrm{conditions}, \mathrm{vs} \mathrm{is} \mathrm{found} \mathrm{to} \\ \mathrm{be} 400{\mathrm{ms}}^{–1}. \mathrm{What} \mathrm{is} \mathrm{the} \mathrm{new} \mathrm{value} \mathrm{of} \mathrm{vs} \mathrm{if} \mathrm{the} \mathrm{the} \\ \mathrm{pressure} \mathrm{were} \mathrm{reduced} \mathrm{by} 5\%? \end{gathered}$$

Which of the following statement is/are true of interference of waves?

I. It is a result of superposition of two or more waves.

II. It can be explained using corpuscular nature of light.

III. It can be explained using wave nature of light waves

IV. Only the wave-particle duality of light can be used to explain interferences.

V. It produces bright and dark fringes.

Resistance of a material depends on the following except

An X-ray tube takes a current of 7.0 mA and operates at a potential difference of 80 kV. What power is dissipated?

Which of the following describes what occurs in the fission process?

The coordinate of a particle in meters is given by x(t) = 16t − 3.0t³, where the time t is in seconds. The particle is momentarily at rest at t =

The maximum efficiency of a heat engine which operates between the measured temperatures of 227 °C and 727 °C is

The stopping potential for electrons ejected by 6.8 ×10¹⁴ Hz electromagnetic radiation incident on a certain sample is 1.8V. The kinetic energy of the most energetic electrons ejected and the work function of the sample, respectively, are

When a kaon decays via the strong interaction the products must include a:

A particle with spin angular momentum is called a:

Which of the following consists entirely of vector quantities?

Two forces each of 10N act on a body, one towards the north and the other towards the east. The magnitude and the direction of the resultant force are

The main reason for making the cover of a vacuum flask airtight is to prevent heat loss by

A cell can supply currents of 0.4A and 0.2A through a 4.0Ω and 10.0Ω resistors respectively. The internal resistance to the cell is

A working electric motor takes a current of 1.5A when the p.d. across it is 250V. if its efficiency is 80%, the power output is

At what frequency would a capacitor of 2.5µF used in radio circuit have a reactance of 250Ω?

A certain radioactive source emits radiations that were found to de deflected by both magnetic and electric fields. The radiations are