A. I believe this might be the answer but
6 J/60 J= .1
.1 x 100= 10%
b. I'm not sure of this question
19. I'm not sure if I did this correct way or if there is a better way (I'm rusty)
300 J/.50 %= 600
600/100= 6 (answer)
20. (200 J)(.75%) = 150 (answer)
Check:
Efficiency: output/input x 100
150 J/200 J= .75
.75 x 100= 75%
The answer is B. Oil Spill
Answer:
1.54 kg
Explanation:
mass of first block (m) = 0.76 kg
acceleration due to gravity (g) = 9.8 m/s
what is the mass (m) of the second block
mg = kx
where m is the mass, g is the acceleration due to gravity, k is the
spring constant and x is the extension
0.76 x 9.8 = kx
7.5 = kx
k = 7.5/x ... equation 1
- when a second block is attached to the first one the amount of stretch triples (this means that extension (x) = 3x)
therefore the new mass becomes m + 0.76 and the extension
becomes 3x
with the new mass and extension, mg = kx now becomes
(m+0.76)g = k(3x) ... equation 2
Recall that k = 7.5/x from equation 1, substituting this value of k into
equation 2 we have
(m+0.76)g =
× (3x)
(m+0.76)g = 7.5 × 3
substituting the value of g = 9.8 m/s^{2}
(m + 0.76) x 9.8 = 7.5 x 3
m + 0.76 = 22.5 ÷ 9.8
m + 0.76 = 2.3
m = 2.3 - 0.76 = 1.54 kg
Answer:
D
Explanation
take 5x2000 and J is the unit for power therfore it cant be A and B and C are not 10,000.
Question; what causes earthquakes?
Answer; what causes earthquakes are mainly when rocks are underground and then suddenly break along a fault.