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suppose a skydiver (mass = 75kg) is falling toward the Earth. When the skydiver is 100m above the earth he is moving 60m/s. At this point calculate the skydivers.......

Gravational potential energy


Kinetic energy


Respuesta :

Blacklash

Answer:

Kinetic energy  = 135 kJ

Potential energy = 73.5 kJ

Explanation:

 Mass of sky diver = 75 kg

  Velocity = 60 m/s

   Height = 100 m

 Kinetic energy is given by the expression, [tex]KE = \frac{1}{2} mv^2[/tex], where m is the mass and v is the velocity.

  So Kinetic energy  = [tex]\frac{1}{2} *75*60^2=135000J=135kJ[/tex]

 Potential energy is given by the expression, PE =mgh, m is the mass, g is the acceleration due to gravity value and h is the height.

 So, Potential energy = 75*9.8*100 = 73500J = 73.5 kJ

kudzordzifrancis
From the question,
The mass of the skydiver,

[tex]m=75kg[/tex]


The height from the Earth at which the skydiver is before falling,

[tex]h=100m[/tex]


Velocity, V of the skydiver

[tex]=60m {s}^{ - 1} [/tex]



Let us take acceleration due to gravity to be ;
[tex]g = 10m {s}^{ - 2} [/tex]


The mass of the skydiver, m=75kg

The height from the Earth at which the skydiver is before falling, h=100m

Velocity, V of the skydiver =60m/s


Potential energy, P.E can be calculated from the relation;
P.E = mgh

[tex]P.E =75kg \times 10m {s}^{ - 2} \times 100m[/tex]
P.E =75000 J

Therefore, the gravitational potential energy of the skydiver is 75000 J


Kinetic energy,K.E
[tex] = \frac{1}{2}m {v}^{2} [/tex]

[tex] = \frac{1}{2} \times 75 kg\times ( {60})^{2} m {s}^{ - 1} [/tex]

=135000 J

Hence the kinetic energy of the Skydiver is 135000 J