Heena Sharma, Shubhankat Vats and, Rashmi Gupta Solutions for Chapter: Periodic Tests, Exercise 14: SAMPLE QUESTION PAPER

An element $\mathrm{X}$ with atomic number $12$ and atomic mass $26$. Diagrammatically, show the distribution of electrons in the orbits and the nuclear composition of the neutral atom of the element. Also, determine the valency of the element.

If element $\mathrm{X}$ $($electronic configuration $2, 8, 2)$ combines with element $\mathrm{Y}$ (with electronic configuration $2, 8, 7$). What will be the formula of the compound thus formed? Explain.

State Newton’s third law of motion and give one example to illustrate the law.

Give reasons for the following observation.

When a boy jumps out of a boat, the boat moves backwards.

Give reasons for the following observation.

The passengers sitting in a bus fall backward when the bus starts to move suddenly.

If the engine of a car provides an acceleration of $2 \mathrm{m}/{\mathrm{s}}^2$ To start it from rest, then assuming the mass to be roughly $1000 \mathrm{kg}$. Calculate the force provided by the engine.

If the engine of a car provides an acceleration of $2 \mathrm{m}/{\mathrm{s}}^2$ to start it from rest, then assuming the mass to be roughly $1000 \mathrm{kg}$. Calculate the velocity after $10 \mathrm{s}$.

If the engine of a car provides an acceleration of $2 \mathrm{m}/{\mathrm{s}}^2$ to start it from rest, then assuming the mass to be roughly $1000 \mathrm{kg}$. Calculate the time after which the car comes to rest if the engine is turned off after $15 \mathrm{s}$. (Take, frictional force $= 15 \mathrm{N}$)