Consider the following statements. (1) Hot chamber machine is used for casting zinc, tin and other low melting alloys (2) Cold chamber machine is used for die casting of ferrous alloys (3) Rapid cooling rate in die casting produces high strength and quality in many alloys Which of these statements are correct?

The influence of shape of aggregate in strength and workability of concrete are given below in statements S1, S2, S3 and S4. Which of the statements are correct? S1: Rounded aggregate produces concrete with high workability and low strength. S2: Angular aggregate produces concrete with high workability and low strength. S3: Rounded aggregate produces concrete with low workability and high strength. S4: Angular aggregate produces concrete with low workability and high strength.

A

S3 and S4

B

S2 and S3

C

S1 and S2

D

S1 and S4

Which of the following statements are true regarding cold and hot deserts: (a) Hot deserts have high temperature while cold deserts have low temperature. (b) hot deserts are battered by sun and are sandy. Cold deserts have ice and snow covered ground. (c) Hot deserts are red or orange while cold deserts are gray. (d) Hot and cold deserts experience a significant seasonal effect.

A

(a) and (b)

B

(a), (b) and (c)

C

(a) and (c)

D

(a), (b), (c) and (d)

Assertion (A): Aluminium alloys are cast in a hot chamber die casting machine. Reason (R): Aluminium alloys require high melting when compared to zinc alloys.

A

Both A and R individually true and R is the correct explanation of A.

B

Both A and R individually true and R is not the correct explanation of A.

C

A is true but R is false

D

A is false but R is true

In cold chamber die casting, rapid cooling of the castings is done as compared to the hot chamber die casting.

A

True

B

False

S₁: Different countries show different pattern of growth.
P: Many others have a high birth rate with a low death rate.
Q: Some have a high birth rate and still have a high death rate.
R: The developing countries show the most rapid growth rate.
S: Some others like the European nations, have a low birth rate and a low death rate.
S₆: Compared to this in Europe the growth rate is low.

The Proper sequence should be:

A

PQSR

B

QSPR

C

RSQP

D

SPQR

Consider the following statements for cooling towers: 1. Cooling tower is an artificial device used to cool the hot cooling water coming out of condenser more effectively. 2. The amount of water usually lost with induced draft cooling tower ranges from 5% to 6% by evaporation. 3. The amount of water usually lost with induced draft cooling tower ranges from 7% to 8% by drift losses. 4. The rate of evaporation of water and its cooling effect on the remaining water depends upon the relative humidity of air passing through the tower. Which of the above statements are correct?

A

1 and 4 only

B

1 and 3 only

C

2 and 3 only

D

1, 2, 3 and 4

Which of the following statements is/are correct? 1. A fuse wire is made of 37% lead and 63% tin 2. A fuse wire is made of 63% lead and 37% tin 3. A fuse wire has high resistance and low melting point 4. A fuse wire has low resistance and high melting point

A

1, 4 are correct statements

B

1, 3 are correct statements

C

2, 3 are correct statements

D

2, 4 are correct statements

In two alloys A and B the ratio of Zinc and Tin is 5 : 2 and 3 : 4 respectively. 7 kg of the alloy A and 21 kg of the alloy B are mixed together to form a new alloy. What will be the ratio of Zinc and Tin tin the new alloy ?

A

2 : 1

B

1 : 2

C

2 : 3

D

1 : 1

The melting temperature of non-ferrous alloys, to be casted in a cold chamber die casting machine are of?

A

low melting temperature

B

high melting temperature

C

two eutectic points

D

three eutectic points

The chances of defects in the castings by cold chamber die casting are more than the castings produced by hot chamber die casting.

A

True

B

False

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