Answer:
3.32 m/s
Explanation:
From the law of conservation of energy, the sum of mechanical and kinetic energy should be equal to the 10 J given. Potential energy is given by mgh where m is mass, g is acceleration due to gravity and h is the height. For this case, 
and l is string length, given as 2 m, \theta is given as 50 degrees. Kinetic energy is given by 
and it is this velocity that is unknown.
Answer:
Decreased by a factor of 4.5
Explanation:
"We have Newton formula for attraction force between 2 objects with mass and a distance between them:
where 
is the gravitational constant on Earth. 
are the masses of the object and Earth itself. and R distance between, or the Earth radius.
So when R is tripled and mass is doubled, we have the following ratio of the new gravity over the old ones:
Since 
and 
So gravity would have been decreased by a factor of 4.5
Answer:
We know that pole is the point where the strength of the magnet is maximum. So more and more iron particles will be attracted at poles of a magnet when we bring a magnet near the iron particles. We will observe the crowdness of particles at the ends of magnet. This indicates the presence of two poles in a magnet. Hence poles are present in a magnet in pair. If a magnet is divided into two parts, each part also possesses a pair of poles.
Two properties of a magnet are: A magnet always has two poles: north pole and south pole. Like magnetic poles repel each other and unlike magnetic poles attract each other.
Wind turbines take the kinetic energy from the wind and convert it into mechanical energy which can be used for different stuff such as a generator which converts it into electrical energy.
Have a wonderful day!
Answer:
a) The maximum potential difference the wet human body can take = 5.88 V
b) This value is very much lower than the normal voltage of household outlets (120 V) and isn't in the same range at all.
This means one should be very careful operating electrical appliances (even at home) while the body is wet.
Explanation:
From Ohm's law, V = IR
The resistance of the body when the body is wet = 1.2 kΩ = 1200 Ω
Maximum safe current that the body can withstand = 4.90 mA = 0.0049 A
Maximum voltage the body can withstand while wet = (Maximum safe current that the body can withstand) × (Resistance of the body when the body is wet) = 0.0049 × 1200 = 5.88 V
b) This value is still very much lower than the normal voltage of household outlets (120 V) and isn't in the same range at all.
This means one should be very careful operating electrical appliances (even at home) while the body is wet.
