The work done can be calculated using the equation:
Work = Force x Distance = Change in kinetic energy
The kinetic energy is derived using the following formula: KE = (1/2)*m*v^2
Thus, the change in kinetic energy is calculated as (1/2)*m*(Vf)^2 - (1/2)*m*(Vo)^2
Where:
Vf represents the final speed = 90 kph = 25 m/s
Vo denotes the initial speed = 72 kph = 20 m/s
By substituting in the given values:
Work = (1/2)*2500*(25^2) - (1/2)*2500*(20^2) = 281250 J, which can also be represented as 2.8 x 10^5 Joules.
The correct choice among the options is A.
I will assume the girl is on the right while the boy is on the left.
The net force represents the total of all forces acting on an object, factoring in negatives.
Let the force from the boy be denoted as b. We’ll apply the formula F = ma.
b + 3.5 = 0.2(2.5)
This reduces to a straightforward algebraic problem. By solving, we find that the boy is applying a force of -3N to the left.
Answer:
Arrangement A facilitates a greater rate of heat transfer
Explanation:
The rate of heat conduction between two materials differing in temperature adheres to the formula
This equation demonstrates that
- An enlarged equivalent cross-sectional area between the two materials will enhance the rate of heat transfer.
- A reduction in the length of the medium will also amplify the rate of heat transfer
Arrangement A features a shorter transfer medium and a larger equivalent cross-sectional area, since the two rods are set up in a parallel arrangement.
Conversely, Arrangement B has a longer transfer medium and a smaller cross-sectional area, as the two rods are placed end to end
To address this issue, we apply the de Broglie equation written as:
λ = h/mv
where h equals 6.626×10⁻³⁴ J·s
Solving for m, we substitute for v, which is 46.9 m/s:
9.74 × 10⁻³⁵ m = 6.626×10⁻³⁴ J·s / (m)(46.9 m/s)
Thus, we find that m = 0.145kg
Vx = 2*cos30 = 1.73 m/s
In other terms:
D = Vo*t = 1.4 * 21 = 31.5 m. at 30 degrees.
Dy = 31.5*sin30 = 15.75 m.
