(a)
consider the motion of the tennis ball. lets assume the velocity of the tennis ball going towards the racket as positive and velocity of tennis ball going away from the racket as negative.
m = mass of the tennis ball = 60 g = 0.060 kg
v₀ = initial velocity of the tennis ball before being hit by racket = 20 m/s
v = final velocity of the tennis ball after being hit by racket = - 39 m/s
ΔP = change in momentum of the ball
change in momentum of the ball is given as
ΔP = m (v - v₀)
inserting the above values
ΔP = (0.060) (- 39 - 20)
ΔP = - 3.54 kgm/s
hence , magnitude of change in momentum : 3.54 kgm/s
The most common difference between the two is that while conductors allow free flow of electrons from one atom to another, insulators restrict free flow of electrons. Conductors allow electrical energy to pass through them, whereas insulators do not allow electrical energy to pass through them.
The answer is: " 5 g / cm³ " .
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Explanation:
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Density = mass divided by volume ; or: "D = m / V " ;
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and is expressed as: "mass per unit volume" ;
The mass, "m", is expressed in units of "g" (grams) ; and
the volume, "V" is expressed in units of "cm³ " or "mL" ; ("cm³ ", in this case);
{Note the exact conversion: " 1 cm³ = 1 mL " .} .
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So, if: the mass, "m = 100 g" {given} ;
and the volume, " V = 20 cm³ " {given} ;
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Plug these values into the formula/equation to solve for the density, "D" ;
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D = m / V = (100 g) / (20 cm³)
= (100 ÷ 20) g / cm³ = 5 g /cm³ .
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The answer is: " 5 g / cm³ " .
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C because the length & the path i took determines the distance .
Massive stars may explode with such intensity that they become part of other objects, such as neutron stars, pulsars, and black holes.
These massive stars are at least 8 times as massive as the Sun and when they explode, a supernova is created.
