(1) friction is the force resisting the relative motion of solid surfaces , fluid layers and material elements sliding against each other.
(2) gravity is a science fiction .
(3) Resistance ::: is a property of a conductor by which the passage of current is opposed causing electric energy to be transformed into heat .
(4) viscosity is the quantity that describes a fluid.
(5)
Answer:
True
Explanation:
When a nuclear power plants ends its operating life, it is necessary to dispose correctly all the radioactive material left from the operations of the power plant.
In fact, apart from the fuel rods (which contain the uranium that is the fuel of the nuclear reactions), other materials of the core (such as the vessel) becomes radioactive due to the prolonged exposure to the products of nuclear reactions in the core.
As a result, all these materials remain radioactive for very long time (hundreds or thousands of years). It is therefore important to dispose them correctly, in proper sealed containers which are able to shield the radiation emitted by these radioactive element (alpha, beta and gamma radiation).
Therefore, "waste from nuclear power plants must be disposed of in radioactively shielded storage containers" is a correct statement.
We use 1/o + 1/i = 1/f where o is the distance of the object, i as distance of the image and f is the focal length.
Substituting, <span>1/ 100 + 1 / i = - 1 /25 </span>
<span>i = - 20 cm </span>
<span>For the case of the problem,</span>
<span>o = (20 + 30) = 50 cm </span>
<span>f = 33.33. </span>Using 1<span> / i + 1 / o = 1/f , </span><span> </span><span>i = 100 cm </span>
<span>M = magnification = - i / o </span>
<span>m1 = -(-20)/100 = 20/100 = 0.2 </span>
<span>m2 = -100/50 = -2 </span>
<span>M = m1*m2 = -2 x 0.2 = -0.4.</span>
Answer:
V = 0.32 m /s
Explanation:
Momentum of the man on the sledge along with sledge
= (80+8) x 10 = 880 kg. m/s When the man jumps off the sledge , the velocity of the sledge will remain intact at 10 m/s
When the sledge hits the boulder and bounces back the momentum of the sledge - boulder system will remain conserved .
change in momentum of sledge = 8 x (10 +6 )
= 128 kg m/s
Change in the momentum of boulder
= 400 V -0
= 400V
400V = 128
V = 0.32 m /s
