Explanation:
Since, it is mentioned the there occurs no change in the temperature. This also means that there will occur no change in thermal energy of the system.
Hence, = 0. And, as
= 0 then there will be no work involved. This means that total energy added to the house will return to the outside air as heat.
Therefore,
Q = -(19000 J + 2000 J)
= -21000 J
or, |Q| = 21000 J
Thus, we can conclude that the magnitude of the energy transfer between the house and the outside air is 21000 J.
Answer:
B = 191.26 cm
θ = -14.73°
Explanation:
given,
magnitude of the first displacement(A) = 146 cm
at an angle of 124°
resultant magnitude = 137 cm
and angle made with x-axis by the resultant(R) = 32.0°
component of A in X and Y direction
A x = A cos θ = 146 cos 120° = -73 cm
A y = A sin θ = 146 sin 120° = 126.4 cm
now component of resultant in x and y direction
R x = 137 cos 35°
= 112.2 cm
R y = 137 sin 35°
= 78.6 cm
resultant is the sum of two vectors
R = A + B
R x = A x + B x
B x = 112.2 - (-73) = 185.2 cm
B y = R y - A y
B y = 78.6 - 126.4 = -47.8 cm
magnitude of B
B =
B =
B = 191.26 cm
angle
θ = -14.73°
Answer:
Explanation:
Use the one-dimensional equation
which says that the final velocity of an object is equal to the object's initial velocity plus its acceleration times time. We are looking for time. That means the equation looks like this:
0 = 30 + (-4)t and
-30 = -4t so
t = 7.5 sec