F(of spring)=230x=ma=3.5(5)=17.5=230x; x=0.07m.
Answer:
copper will have more change in temperature as compare with aluminum
Explanation:
Hot piece of copper is made in contact with cold piece of aluminium
So here thermal energy transfer will take place from copper to aluminium
so by energy conservation we can say that heat given by copper is same as the heat absorbed by aluminium.
now we have
here we know that
= specific heat capacity of copper
= specific heat capacity of aluminum
given that specific heat capacity of aluminium is more than double that of copper
so we can say
so here if the mass of copper and aluminium is same then
so temperature change of copper is twice the temperature change of aluminium
So copper will have more change in temperature as compare with aluminum
As long as all the waves stay in the same medium, the intensity of
any waves ... electromagnetic or mechanical ... decrease in proportion
to the square of the distance.
If the distance increases to 3 x the original distance, then the intensity
changes to 1/3² or 1/9 of the original intensity.
I suppose choice-'d' is the correct one, but I have to tell you that
the phrase "nine times as low" is mathematically meaningless,
and it really grinds my gears.
Resistance can be calculated by Ohm's law
As per ohm's law we will have
here we will have
voltage = 220 volts
current = 10 A
So by the above formula we will have
So resistance of the bulb is 22 ohm.
Answer: 909 m/s
Explanation:
Given
Mass of the bullet, m1 = 0.05 kg
Mass of the wooden block, m2 = 5 kg
Final velocities of the block and bullet, v = 9 m/s
Initial velocity of the bullet v1 = ? m/s
From the question, we would notice that there is just an object (i.e the bullet) moving before the collision. Also, even after the collision between the bullet and wood, the bullet and the wood would move as one object. Thus, we would use the conservation of momentum to solve
m1v1 = (m1 + m2) v, on substituting, we have
0.05 * v1 = (0.05 + 5) * 9
0.05 * v1 = 5.05 * 9
0.05 * v1 = 45.45
v1 = 45.45 / 0.05
v1 = 909 m/s
Thus, the original velocity of the bullet was 909 m/s
