This is a speed/time graph.
The slope of the graph at each point is the time rate of change of speed
at that point, and THAT's the definition of the magnitude of acceleration.
The slope of the curve is zero at both ' A ' and ' B ', so acceleration is
zero at both of those points.
That seems to be exactly what choice-c says.
Answer:
The sum of the lengths of the sides is 2292 yards and the sum of the lengths of the triangle is 3056 yards
Explanation:
Since y represents the length of fence that is opposite (parallel) to the river and x represent the length of fence perpendicular to the river.
Therefore since we can use 3,056 yards of fencing
Side perpendicular to the river = x and,
Side opposite to the river = y = 3056 - 2x
The area of the rectangle formed (A) = Perpendicular side × Parallel side
∴ A = x(3056 - 2x) = 3056x - 2x²
A = 3056x - 2x²
To maximize the area, A' (dA/dx) = 0
∴ A' = 3056 - 4x = 0
3056 - 4x = 0
4x = 3056
x = 764 yards
y = 3056 - 2x = 3056 - 2(764) = 1528 yards.
Side perpendicular to the river = 764 yards and,
Side opposite to the river = 1528 yards
The sum of the lengths of the sides = 764 + 1528 = 2292 yard and the sum of the lengths of the triangle = 764 + 764 + 1528 = 3056 yards
Mechanical energy E = mgh + 1/2mv²
When he starts, let h = 0 ⇒ E₁ = 1/2mv₁²
When he reaches height h ⇒ E₂ = mgh + 1/2mv₂²
Without friction, energy is conserved at all times.
E₁ = E₂
↓
1/2mv₁² = mgh + 1/2mv₂²
↓
1/2v₁² = gh + 1/2v₂²
↓
gh = 1/2(v₁² - v₂²)
↓
h = (v₁² - v₂²) / (2g)
Answer:
A. 200 J
Explanation:
The initial kinetic energy depends on the initial speed, while the gravitational potential energy depends on the height, both balls are thrown with the same initial speed and from the same height. Therefore, due to the law of conservation of energy, the balls must have the same mechanical energy (the sum of both energies) when both impact the ground. Since the potential energy is zero at this point, its final kinetic energy must also be the same.
Heat always flows from higher temperature to lower temperature. So option A. heat will flow from the air into the coolant is the correct answer.
