Answer:
HENCE (3) IS ANSWER
Explanation:
α =ΔL/(LO×Δ T) or ΔL= α(LO×Δ T)
HERE ΔL IS CHANGE IN LENGTH, Lo is original length , α is coefficient of linear expansion , Δ T is change in temperature
α= 11 x 10 ^-6/°C , Δ T = 19-20 = -1°C
hence
ΔL= 11 x 10 ^-6×10×-1
= - 11×10^-5
MINUS SIGN SHOWS SHORTER
HENCE (3) IS ANSWER
Answer:
Minimum coefficient of kinetic friction between the surface and the block is
.
Explanation:
Given:
Mass of the block = M
Spring constant = k
Distance pulled = x
According to the question:
<em>We have to find the minimum co-efficient of kinetic friction between the surface and the block that will prevent the block from returning to its equilibrium with non-zero speed. </em>
So,
From the FBD we can say that:
⇒ Normal force,
<em>...equation(i)</em>
⇒ Elastic potential energy,
=
<em> ...equation (ii)</em>
⇒ Frictional force,
=
<em> ...equation (iii)</em>
⇒ Plugging (i) in (iii).
⇒
Now,
⇒ As we know that the energy lost due to friction is equivalent to PE .
⇒
<em>...considering PE as</em>
or
.
Arranging the equation.
⇒ 
⇒
<em>...eliminating x from both sides.</em>
⇒
<em>...dividing both sides wit Mg.</em>
Minimum coefficient of kinetic friction between the surface and the block is
.
Purpose of life is to explore and get experience. Another reason is to love and let what makes you happy guide you
<span> The masses have no inertia about their own CM, and "the object" is the two masses. </span>
<span>1. Icm (at point A) = 2mr^2
hope this helps</span>
<span>The life forms of the biosphere are located within Earth's surface.</span>