Answer:
Explanation:
Since all the four charges are equidistant from the position of Q
so here we can assume this charge distribution to be uniform same as that of a ring
so here electric field due to ring on its axis is given as
here we have
x = b
and the radius of equivalent ring is given as the distance of each corner to the center of square
now we have
so the force on the charge is given as
Answer:The highest possible efficiency of this heat engine is 11%
Explanation:
Saturated water temperature at P1, Pressure in Heat addition,
1.1 MPa=185°C +273= 458K
Saturated water temperature at P2, Pressure in Heat rejection,
0.3MPa=133.5°C+ 273=406.5K
The highest possible efficiency of any heat engine is the Carnot efficiency given as
Carnot efficiency, ηmax = 1- (T2/ T1)
1- (406.5K/458K)
1-0.88755=0.112
=11%
Given,
The initial inside diameter of the pipe, d₁=4.50 cm=0.045 m
The initial speed of the water, v₁=12.5 m/s
The diameter of the pipe at a later position, d₂=6.25 cm=0.065 m
From the continuity equation,
Where A₁ is the area of the cross-section at the initial position, A₂ is the area of the cross-section of the pipe at a later position, and v₂ is the flow rate of the water at the later position.
On substituting the known values,
Thus, the flow rate of the water at the later position is 5.99 m/s
Answer:
The acceleration of the object is 20 meters per second square = 20 m/s^2
Explanation:
Recall that acceleration is defined as the change in velocity divided the time it takes for the change. Therefore , if the object accelerates from rest (zero velocity) to 70 m/s , the change in velocity is (70 m/s - 0 m/s = 70 m/s)
which divided by the 3.5 seconds it took for the change, gives:
acceleration = (70 m/s / 3.5 s ) = 20 m/s^2
Answer:
No temperature change occurs from heat transfer if ice melts and becomes liquid water (i.e., during a phase change). For example, consider water dripping from icicles melting on a roof warmed by the Sun. Conversely, water freezes in an ice tray cooled by lower-temperature surroundings.
Explanation:
Energy is required to melt a solid because the cohesive bonds between the molecules in the solid must be broken apart such that, in the liquid, the molecules can move around at comparable kinetic energies; thus, there is no rise in temperature. Similarly, energy is needed to vaporize a liquid, because molecules in a liquid interact with each other via attractive forces. There is no temperature change until a phase change is complete. The temperature of a cup of soda initially at 0ºC stays at 0ºC until all the ice has melted. Conversely, energy is released during freezing and condensation, usually in the form of thermal energy. Work is done by cohesive forces when molecules are brought together. The corresponding energy must be given off (dissipated) to allow them to stay together Figure 2.
The energy involved in a phase change depends on two major factors: the number and strength of bonds or force pairs. The number of bonds is proportional to the number of molecules and thus to the mass of the sample. The strength of forces depends on the type of molecules. The heat Q required to change the phase of a sample of mass m is given by
Q = mLf (melting/freezing,
Q = mLv (vaporization/condensation),
where the latent heat of fusion, Lf, and latent heat of vaporization, Lv, are material constants that are determined experimentally.
