Answer:
a. 37.7 kgm/s b. 0.94 m/s c. -528.85 J
Explanation:
a. The initial momentum of block 1 of m₁ = 1.30 kg with speed v₁ = 29.0 m/s is p₁ = m₁v₁ = 1.30 kg × 29.0 m/s = 37.7 kgm/s
The initial momentum of block 2 of m₁ = 39.0 kg with speed v₂ = 0 m/s since it is initially at rest is p₁ = m₁v₁ = 39.0 kg × 0 m/s = 0 kgm/s
So, the magnitude of the total initial momentum of the two-block system = (37.7 + 0) kgm/s = 37.7 kgm/s
b. Since the blocks stick together after the collision, their final momentum is p₂ = (m₁ + m₂)v where v is the final speed of the two-block system.
p₂ = (1.3 + 39.0)v = 40.3v
From the principle of conservation of momentum,
p₁ = p₂
37.7 kgm/s = 40.3v
v = 37.7/40.3 = 0.94 m/s
So the final velocity of the two-block system is 0.94 m/s
c. The change in kinetic energy of the two-block system is ΔK = K₂ - K₁ where K₂ = final kinetic energy of the two-block system = 1/2(m₁ + m₂)v² and K₁ = final kinetic energy of the two-block system = 1/2m₁v₁²
So, ΔK = K₂ - K₁ = 1/2(m₁ + m₂)v² - 1/2m₁v₁² = 1/2(1.3 + 39.0) × 0.94² - 1/2 × 1.3 × 29.0² = 17.805 J - 546.65 J = -528.845 J ≅ -528.85 J
Answer:
Second one
Explanation:
Lying on the floor is something you can do with the least amount of energy
Answer:
-2.8 m/s²
Explanation:
Acceleration: This can be defined as the rate of change of velocity The S. I unit of acceleration is m/s²
Using the equation of motion,
v² = u² + 2as................... Equation 1
Where v = Final velocity, u = initial velocity, a = acceleration, s = distance,
Given: v = 6.0 m/s, u = 8.0 m/s, s = 5.0 m.
Substituting into equation 1
6² = 8²+2(a)5
36 = 64 + 10a
10a = 36-64
10a = -28
10a/10 = -28/10
a = -2.8 m/s²
Note: a is negative because because the skater decelerate on the rough ice
Hence the magnitude of her acceleration is = -2.8 m/s²
(c) is the correct choice.
El Nino (a), Earth's orbit (b), and solar energy output (d) are all "natural" occurrences. You can't do a thing aboutum.
Fossil fuels ... or, more precisely, humanity's use of vast quantities of fossil fuels as a convenient source of huge quantities of energy ... and the subsequent increase of Carbon Dioxide in the planet's atmosphere, is not the result of "natural" processes. It's the result of human efforts to <em>alter and control</em> Nature, through <em>artificial</em> processes.
Answer:
$893
Explanation: the complete question should be
The clothes washer in your house consumes 470 kWh of energy per year. Price of the washer is $360 and the lifetime of the washer is 10 yrs. Energy price in your city is 9 cents per kWh. What is the lifecycle cost of the clothes washer? (assume a maintenance cost of $11 per year)
SOLUTION
Given:
The clothes washe power consumption (PC) is 470 kWh
Price of the washer (P) is $360
lifetime of the washer (L) is 10 yrs
Energy price in the city (E) is 9 cents per kWh (Covert to $ by dividing 100)
maintenance cost (M) is $11 per year
Lifecycle cost = P + (PC × L × E) +M + L
Lifecycle cost = $360 + (470kWh × 10years × 9cents/100) + ($11 × 10years)
=$893
