Answer:
112.58
Explanation:
The Coefficient of Performance of any system is denoted by COP=Q/W, where Q is the useful heat supplied or removed and W is the work required by the system. According to the first law of thermoddynamics Qh= Qc + W, where Qh is the heat transfered to the hot reservoir and Qc is the heat collected from the cold reservoir. Substituting the values for W and apllying the limitation for maximum theoretical efficiency we end up with the eqution shown below.
The Coefficient of Performance of air conditioner or COP is denoted by
COP(cool) = Tc/(Th- Tc)
where Tc: the lowest temperature
Th: the highest temperature
converting the values to Kelvin and adding them in the above equation
COP(cool) = (25+273)/((34+273)-(25+273))
= 298/(307-298)
= 298/9 = 33.11
From the question, it is stated that COP=SEER/3.4
hence, SEER= COP * 3.4
SEER= 33.11 * 3.4 = 112.58
2.3 seconds
Ignoring air resistance, the flight time is merely a function of gravity and vertical velocity. The vertical velocity will be the initial velocity multiplied by the sine of the angle above the horizon. So:
V = sin(72)*12 m/s
V = 0.951056516 * 12 m/s
V = 11.4126782 m/s
Gravitational acceleration is 9.8 m/s, so divide the vertical velocity by gravitational acceleration to get how long it takes for the ball to reach its apex.
11.4126782 m/s / 9.8 m/s^2 = 1.164559 s
And the old saying "What goes up, must come down" really applies here. And conveniently, it's also symmetric, in that the time it takes to fall will match the time it takes to reach its apex. So multiply the time by 2.
1.164559 s * 2 = 2.329117999 s
Rounding the result to 2 significant figures gives 2.3 seconds.
Answer:
ω' = 2.5 rad/s
Explanation:
mass of cockroach, m = 4 kg
mass of disk, M = 6 kg
Radius of disc= R
initial angular velocity, ω = 2 rad/s
Let the final angular velocity is ω'
As no external torque is applied, so the angular momentum is constant.
Angular momentum = Moment of inertia x angular velocity
I ω = I' ω'
ω' = 2.5 rad/s
Let A = i+j+k be a vector and B = 3 be any scalar,
Multiplying A and B,
AB = (i+j+k)3 = 3i+3j+3k
Which is a new vector whose direction is same as the old but it's 3 times greater in length than the old vector(i+j+k).
Now, dividing A and B,
A/B = (i+j+k)/3 =
Which is again a new vector whose direction is same as the old but now it's 1/3 times small in length than the old vector.
Direction is same because we multiplied by positive scalar. If we multiply A by suppose -1, -4, -1000000 or any negative number, it's direction will reverse.
Thus, if we multiply a vector with scalar, it's length increases. If we divide, it shrinks.