Answer:
2.2nC
Explanation:
Call the amount by which the spring’s unstretched length L,
the amount it stretches while hanging x1
and the amount it stretches while on the table x2.
Combining Hooke’s law with Newton’s second law, given that the stretched spring is not accelerating,
we have mg−kx1 =0, or k = mg /x1 , where k is the spring constant. On the other hand,
applying Coulomb’s law to the second part tells us ke q2/ (L+x2)2 − kx2 = 0 or q2 = kx2(L+x2)2/ke,
where ke is the Coulomb constant. Combining these,
we get q = √(mgx2(L+x2)²/x1ke =2.2nC
First we have to calculate the time taken to travel the distance 30 m, is
.
Now from equation of motion,
Given, 
.
As object starts from rest, so u = 0.
Substituting these values in above equation, we get
.
Thus, the acceleration is 
Answer:
Explanation:
As we know that moment of force is given as
now we have
now from above formula we have
here we know that
so we have
Answer:
150 million kilometres
Explanation:
The astronomical unit (symbol: au, or AU or AU) is a unit of length, roughly the distance from Earth to the Sun and equal to 150 million kilometres (93 million miles) or 8.3 light minutes.
Answer:
Option B is correct.
Explanation:
Potential energy or chemical potential energy is used to Cook food which is then converted into thermal energy. The type of energy used also depends upon the type of cooking appliances used.
For e.g. stove convert potential energy to thermal energy.
