Answer:
Explanation:
Let the bigger crate be in touch with the ground which is friction less. In the first case both m₁ and m₂ will move with common acceleration because m₁ is not sliding over m₂.
1 ) Common acceleration a = force / total mass
= 234 / ( 25 +91 )
= 2.017 m s⁻².
2 ) Force on m₁ accelerating it , which is nothing but friction force on it by m₂
= mass x acceleration
= 25 x 2.017
= 50.425 N
The same force will be applied by m₁ on m₂ as friction force which will act in opposite direction.
3 ) Maximum friction force that is possible between m₁ and m₂
= μ_s m₁g
= .79 x 25 x 9.8
= 193.55 N
Acceleration of m₁
= 193 .55 / 25
= 7.742 m s⁻²
This is the common acceleration in case of maximum tension required
So tension in rope
= ( 25 +91 ) x 7.742
= 898 N
4 ) In case of upper crate sliding on m₂ , maximum friction force on m₁
= μ_k m₁g
= .62 x 25 x 9.8
= 151.9 N
Acceleration of m₁
= 151.9 / 25
= 6.076 m s⁻².
Answer:
(c) 16 m/s²
Explanation:
The position is
.
The velocity is the first time-derivative of <em>r(t).</em>
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The acceleration is the first time-derivative of the velocity.

Since <em>a(t)</em> does not have the variable <em>t</em>, it is constant. Hence, at any time,

Its magnitude is 16 m/s².
Very high-energy objects and events spit out very high-energy photons, so the instrument you need in order to detect them is the X-ray telescope. <em>(C) </em>
Inconveniently, X-ray telescopes only work when they're up in orbit, because X-rays get seriously soaked up in Earth's atmosphere, and most of them never make it down to the surface ... (lucky for us !) .
Answer:
0
Explanation:
The overall charge on this atom is 0.
To find the charge on an atom;
charge = number of protons - number of electrons.
Note:
- Protons are the positively charged particles in an atom
- Electrons are the negatively charged particles in an atom
- Neutrons carries no charges on them.
Since the atom is made up of equal number of protons and electrons, the charge on it is 0.
If the number of electrons is more, the atom will be negatively charge but if the number of protons is more, it will be positively charged.