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stepan [7]
3 years ago
8

Um corpo de massa 2,5kg é lançado verticalmente para cima. Se o sistema for considerado conservativo e no instante em que ele é

lançado sua energia mecânica vale 150 Joules, qual o valor para a energia mecânica no ponto de altura máxima que este corpo atinge, em joules. Considere g = 10m/s2?
Physics
1 answer:
kvv77 [185]3 years ago
7 0

Answer:

Energia mecânica = 300 Joules

Mechanical Energy = 300 Joules

Explanation:

given

m = 2.5kg

g=10m/s²

h=?

K.E = P.E

K.E = 150Joules

¹/₂mv² = m ×g ×h

150 J = 2.5 × 10 × h

h = 150/25

h= 6m

Mechanical energy = K.E + P.E

ME = 2 × 150 J

Mechanical Energy = 300Joules

dado

m = 2,5 kg

g = 10m / s²

h =?

K.E = P.E

K.E = 150Joules

¹ / ₂mv² = m × g × h

150 J = 2,5 × 10 × h

h = 150/25

h = 6m

Energia mecânica = K.E + P.E

ME = 2 × 150 J

Energia mecânica = 300Joules

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Answer:

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To calculate the values in the  question, a deep understanding of perfect inelastic collision is important.

When two bodies undergo inelastic collision, two important parameters must be well understood i.e

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Note, since the direction of movement before collision is due south and  due north respectively we have to represent the velocity using the rectangular coordinate

Hence  p_{12}=(m_{1}+m_{2})v=p_{1}i+p_{2}j\\

(95+90)v=475i+270j\\

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solving for the resultant velocity, we have

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K.E_{final} =\frac{1}{2}(m_{1}+m_{2} )v^{2}\\  K.E_{final} =\frac{1}{2}(95+90)* 3.11^{2}\\ K.E_{final} =894.7J

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K.E =K.E_{final}- K.E_{initial}=894.7-1592.5

K.E =-697.8J

The negative sign indicate a decrease in Kinetic energy

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Why society might initially reject a new scientific theory?
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r^2=1241^2+1003^2-2\times 1003\times 1241cos(36.7)=550112.8295

r = 741.6959 m

3 0
3 years ago
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