The loudness of sound coming from murmur in a quite library is about 30 decibel while that from a car horn is about 120 decibel. The ratio of the amplitudes of vibrations producing these sounds is
A1 : 1
B1 : 2
C1 : 4
D1 : 16
An object vibrates 7200 times in 8 minutes. A girl standing close to the object hears
The given figure shows a girl standing in a garden under the sun.
Which of the following graphs best represents the variation of the length of her shadow with time?
At 12 noon the sun is directly overhead and the length of the shadow should be 0. SOF tells the answer is B but I think it should be C.
Read the given statements and select the correct option.
Statement 1: Groundwater is safe for drinking.
Statement 2: Groundwater is free from soluble impurities.
ABoth statements 1 and 2 are correct and statement 2 is the correct explanation of statement 1.
BBoth statements 1 and 2 are correct but statement 2 is not the correct explanation of statement 1.
CStatement 1 is correct but statement 2 is incorrect.
DBoth statements 1 and 2 are incorrect.
SOF tells that the answer is A. But Statement 2 is incorrect as we get Iron, Magnesium and Calcium Sulphates and Oxides dissolved in ground water. I think C should be correct.
Read the given statements and select the correct
Statement-1 : The brightness of the bulb A remains the same after the switch is closed.
Statement-2 : The voltage across elements in parallel is the same.
A Both statements-1 and 2 are true and statement-2 is the correct explanation of statement-1.
B Both statements-1 and 2 are true but statement-2 is not the correct explanation of statement-1.
C Statement-1 is true and statement-2 is false.
D Both statements-1 and 2 are false.
I think answer is A
Which of the following is correct regarding the impact of deforestation?
(i) Plants of medicinal values found in the forest are lost.
(ii) Fewer trees are left around to hold the soil together, resulting in soil erosion.
(iii) Global warming occurs as there are fewer trees to absorb carbon dioxide.
(iv) The risk of an epidemic outbreak increases, resulting in the death of animals living in forests.
A (i) and (iv)
B (iii) and (iv)
C (i), (ii) and (iii)
D (i), (ii) and (iv)
i have a doubt