Galaxies

Q. What is the name of the galaxy closest to the Milky Way?

1. Andromeda
2. Black eye
3. Sunflower
4. Comet

Q.

Give reasons for the following statement.

A heavier body has higher density.

Q. Explain the Big Bang Theory.

Q.

If there are two bags of equal volume, one containing sugar and other containing cotton, state which one is heavier.
Given the volume of bag$=2{\mathrm{m}}^3$, Density of cotton=$20\mathrm{kg}/{\mathrm{m}}^3$, mass of sugar=$30\mathrm{kg}$

Q.

A block of wood of mass $24kg$ floats in water. The volume of the wood is $0.032m^3$. Taking the density of water as $1000kg/m^3$, calculate the;

1. Volume of the block below the surface of the water, and
2. The density of the wood.

Q.

The weight of water displaced by an iron object is 10 kg. The buoyant force acting on the iron object is___________.

Q.

The weight of a floating body is equal to the ______________.

Q. Which of the following are the properties of an elliptical galaxy?

1. Spiral arms.
2. Larger and older as compared to the spiral galaxies.
3. More stars.
4. Devoid of spiral arms.

Q.

When a body floats, the weight of the floating body is ________ to the weight of the liquid displaced by it.

Q.

The upthrust of a wooden block and on an iron block, of identical dimensions, when fully immersed in water will be________.

Q.

What are the laws of floatation in a liquid? Give some illustrations

Q.

Gold and platinum are denser than lead and iron.

1. True
2. False

Q. Explain the Big Bang Theory.

Q.

A metal box is made up of an alloy of zinc and copper metals. It weighs 20 g and 520 g in a liquid of R .D of 1.4 and water, respectively. The specific gravities of zinc and copper are 7.4 and 8.9, respectively. Arrange the following steps in a proper sequential order to find the masses of metals in the alloy.

(A) Find the weight of the box in a liquid of relative density 1.4 and water along with relative densities of zinc and copper from the given data.
(B) Note down the metals present in the metal box
(c) The relative density of liquid $1.4=\frac{\mathrm{W}-20}{\mathrm{W}-320}$. Find the value of W.

(D) Let the masses and volumes of copper and zinc be ${\mathrm{m}}_{\mathrm{c}}\mathrm{and}{\mathrm{m}}_{\mathrm{z}}$
, ${\mathrm{V}}_{\mathrm{c}}\mathrm{and}{\mathrm{V}}_{\mathrm{z}}\mathrm{respectively}\mathrm{weight}\mathrm{and}\mathrm{volume}\mathrm{of}\mathrm{the}\mathrm{box}\mathrm{respectively}\mathrm{are}({\mathrm{m}}_{\mathrm{z}}+{\mathrm{m}}_{\mathrm{c}})\mathrm{and}({\mathrm{v}}_{\mathrm{z}}+{\mathrm{v}}_{\mathrm{c}})\mathrm{respectivley}.$

(E) substitute $V_c=\frac{m_c}{d_c}and{V}_z=\frac{m_z}{d_z}=\left(\frac{W-m_c}{d_z}\right)tofindthemassesof{m}_{c}and{m}_z$

(F) $\mathrm{the}\mathrm{density}\mathrm{of}\mathrm{alloy}\mathrm{d}=\frac{\mathrm{W}}{\mathrm{W}-320}$

1. BADCFE

2. BCDAFE

3. ABDCEF

4. ABCDEF