Download App

Model Paper 3 — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsModel Paper 33 Marks
Question
How is centripetal force provided in case of the following?
i. Motion of planet around the sun,
ii. Motion of moon around the earth.
iii. Motion of an electron around the nucleus in an atom.
✓

Answer

i. The earth revolves round the sun. The earth is also acted upon by the centripetal force which is provided by the gravitational force of attraction between the sun and the earth.
ii. The motion of moon around the earth is also in circular path. The necessary centripetal force is provided by the gravitational attraction of the earth on the moon.
iii. In an atom, electrons revolve around the nucleus in various circular orbits. The necessary centripetal force for circular motion, is exerted by the electrostatic force of attraction between the positively-charged nucleus and the negatively charged electrons.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Model Paper 3→Model Paper 3 — all question types→Physics STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Can you associate vectors with $(a)$ the length of a wire bent into a loop, $(b)$ a plane area, $(c)$ a sphere? Explain
→
Two identical particles, each having a charge of $2.0 \times 10^{-4} \mathrm{C}$ and mass of 10 g , are kept at a separation of 10 cm and then released. What would be the speeds of the particles when the separation becomes large?
→
Four identical hollow cylindrical columns of mild steel support a big structure of mass 50,000kg. The inner and outer radii of each column are 30 and 60cm respectively. Assuming the load distribution to be uniform, calculate the compressional strain of each column.
→
Two ideal monoatomic gases A and B at 27°C and 37°C are mixed. The number of moles in gas A are 2 and number of moles in gas B are 3. What will be the temperature of the mixture?
→
In an elastic collision of two billiard balls, which of the following quantities remain conserved during the short time of collision of the balls $($i.e., when they are in contact$)$.
  1. Kinetic energy.
  2. Total linear momentum?
Give reason for your answer in each case.
→
The radius of the Earth is $6.37 × 106m$ and its average density is $5.517 \times 10^3kg m^{-3}$. Calculate the mass of earth to correct significant figures.
→
A wheel of mass 10kg and radius 20cm is rotating at an angular speed of 100rev/min when the motor is turned off. Neglecting the friction at the axle, calculate the force that must be applied tangentially to the wheel to bring it to rest in 10 revolutions.
→
Mars has approximately half of the earth’s diameter. When it is closest to the earth it is at about $\frac{1}{2}$ A.U. from the earth. Calculate what size it will appear when seen through the same telescope.
→
A particle is subjected to two simple harmonic motions in the same direction having equal amplitude and equal frequency. If the resultant amplitude is equal to the amplitude of individual motions, what is the phase difference between the motions?
→
Calculate (i) r.m.s. velocity and (ii) mean kinetic energy of one gram molecule of hydrogen at S.T.P. Given density of hydrogen at S.T.P. is $0.09kg-m^{-3}$.
→