<span>Newton established his three laws of motion to understand the motion of objects in a systematic way [ same thing as all Scientists did for human's curiosity ].
His three laws of motion are as follows:
First Law: - </span><span> An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Second Law: - </span><span> The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Third Law: - </span><span>For every action, there is an equal and opposite reaction
Hope this helps!</span>
Option C would be the right one
Gravitational potential energy is energy an object possesses because of its position in a gravitational field. The most common use of gravitational potential energy is for an object near the surface of the Earth where the gravitational acceleration can be assumed to be constant at about 9.8 m/s2.
In Burglar alarm, LDR acts an AND gate.
Answer: C
Explanation
The LDR is light dependent resistor. The principle used in the working of LDR is that the resistance is inversely proportional to the intensity of light falling on the diode.
In burglar alarm, LDR diode is combined with an IC 555.
Normally an LED source is made to be incident on the LDR diode with same intensity such that the resistance will be maintained constant.
As the LDR is connected with IC, the voltage will be high when light is falling on the diode.
The IC will give only two output states that is high and low. This confirms that LDR in burglar alarm act as AND gate.
As the thief enters and crosses the LED light, the intensity of the light falling on the diode will decrease leading to decrease in the voltage which will cause the alarm to beep.
Complete question is;
If the diameter of the black marble is 3.0 cm, and by using the formula for volume, what is a good approximation of its volume?
Answer:
14 cm³
Explanation:
We will assume that this black marble has the shape of a sphere from online sources.
Now, volume of a sphere is given by;
V = (4/3)πr³
We are given diameter = 3 cm
We know that radius = diameter/2
Thus; radius = 3/2 = 1.5 cm
So, volume = (4/3)π(1.5)³
Volume ≈ 14.14 cm³
A good approximation of its volume = 14 cm³