Model Paper 5 Science - Model Paper 5

Which one of the following is not a draught animal?

To prepare a colloidal solution of starch, we should:

The substance which does not form a true solution in water is:

Which of the following are covered by a single membrane?

The common characteristic of xylem tracheids and sieve tubes is that both are:

Assertion (A): For noble gases, valency is zero.
Reason (R): Noble gases have 8 valence electrons.

Assertion (A): Dendrite is a single, long cylindrical process which forms fine branches terminally.
Reason (R): It consists of short processes arising from the cyton.

Assertion (A): Naphthalene, camphor, iodine, ammonium chloride are some common examples of the substances which undergo sublimation.
Reason (R): All solids are first converted to liquids and then gases on heating.

Assertion (A): A boy goes from A to B with a velocity of 20 m/min and comes back from B to A with a velocity of 30 m/min. The average velocity of the boy during the whole journey is zero.
Reason (R): The ratio of speed to the magnitude of velocity when the body is moving in one direction is equal to one.

Summarise the rules for writing of distribution of electrons in various shells for the first eighteen elements.

A truck of mass M is moved under a force F. If the truck is then loaded with an object equal to the mass of the truck and the driving force is halved, then how does the acceleration change?

Two balls of the same size of different materials, rubber and iron are kept on the smooth floow of a moving train.The brakes are applied suddenly to stop the train. Will the balls start rolling? If so, in which direction? Will they move with the same speed? Give reasons for yours answer.

Why the temperature of boiling water does not rise even when heat is continuously supplied to it?

A sound wave has a frequency 2 kHz and wavelength 40 cm. How long will it take to travel 1.6 km?

List the characteristics of cork. How are they formed? Mention their role.

What would happen if the plasma membrane ruptures or breaks down?

Observe the diagram of the cell below answer the following questions.

i. Label the parts of the cell
ii. what function does part 1 perform?
iii. If the organelle 2 is removed from the cell, what effect is it going to make on the functions of the cell?
iv. Identify, whether it is plant cell or animal cell
v. Which structure is called 'Powerhouse of the cells'?

Sony says that the acceleration in an object could be zero even when several forces are acting on it. Do you agree with her? Why?

i. Draw a neat and labelled diagram of the apparatus used to separate components of blue-black ink. Name the process and state the principle involved.
ii. Identify, the physical and chemical changes from the following.
a. Burning of magnesium in air.
b. Tarnishing of silver spoon.
c. Sublimation of iodine.
d. Electrolysis of water.

Write the main function of each of the following.
(a) Plasma membrane
(b) cell wall
(c) Ribosome
(d) Lysosome
(e) Nucleolus
(f) Endoplasmic reticulum

Explain main functional regions of a cell with the help of a diagram.

i. Prove that, if the earth attracts two bodies placed at the same distance from the centre of the earth with equal force, then their masses will be the same.
ii. Mathematically express the acceleration due to gravity in terms of mass of the earth and radius of the earth.
iii. Why is G called a universal constant?

Read the following text carefully and answer the questions that follow:
A solution of a solid in a liquid such as water can be prepared by adding it slowly to water with constant stirring at a certain temperature (room temperature). If the addition process is continued, a stage is ultimately reached in the dissolution process when no more of the solid dissolves. Rather it starts setlling at the bottom of the container such as a glass beaker. The solution at this stage is said to be saturated. The solubility of a solute is always expressed with respect to the saturated solution. It may be defined as the maximum amount of the solute that can be dissolved in 100 g of the solvent to form a saturated solution at a given temperature. Please remember that the role of temperature is very important. If temperature is increased, the solution becomes unsaturated. In case the temperature is decreased, the solution becomes supersaturated. As a result, crust of the solute gets deposited on the surface.
i. What do mean by the term Solubility?
ii. 20 g of a solute are dissolved in 500 g of the solvent. The solubility of the solute is:
iii. When a saturated solution becomes unsaturated?
OR
What do you mean by concentration of solution?

Read the following text carefully and answer the questions that follow:
India has the maximum cattle population in the world. However, their productivity is less than half the productivity of many exotic breeds of cattle. The exotic breeds live in cold countries. They cannot live comfortably in hotter India. The only way to improve the productivity of Indian cattle is to produce hybrids which are acclimitised to Indian conditions and are resistant to most local diseases. For hybridisation exotic bulls are kept in colder climate. Their semen is collected and cryopreserved. The same is sent to various parts of the country for artificial insemination.
i. Mention two exotic breeds of cattle.
ii. Mention two hybrid breeds of cattle.
iii. Mention some factors governing the yield of milk.
OR
When can cattle be inseminated?