# Science

## A student throws a set of keys vertically upward to her sorority sister, who is in a window 2.80 m above. The second student catches the keys 1.80 s later.

A Student Throws A Set Of Keys Vertically Upward To Her Sorority Sister, Who Is In A Window 2.80 M Above. The Second Student Catches The Keys 1.80 S Later. (a) With what initial velocity were the keys thrown? magnitude = m/s (b) What was the velocity of the keys just before they were caught? …

## D11.6 At frequencies of 1, 100, and 3000 MHz, the dielectric constants of ice made from pure water has values of 4.15, 3.44, and 3.20 respectively, while (epsilon”/epsilon’) is 0.12, 0.035, and 0.0009, also respectively. If a uniform plane wave with an amplitude of 100 V/m at z=0 is propagating through such, find the time-average power density z=0 and z=10m for each frequency. The answers are: 27.1 and 25.7W/m^2; 24.7 and 6.31 W/m^2; 23,7 and 8.63 W/m^2. pleace show all steps.

D11.6 At frequencies of 1, 100, and 3000 MHz, the dielectric constants of ice made from pure water has values of 4.15, 3.44, and 3.20 respectively, while (epsilon”/epsilon’) is 0.12, 0.035, and 0.0009, also respectively. If a uniform plane wave with an amplitude of 100 V/m at z=0 is propagating through such, find the time-average …

## 1) Two parallel flat planes of positive charge are separated by a distance d. Plane #1 has charge density 1, and plane #2 has a charge density 2 and 1> 2. (a) In the region between the planes, the magnitude of the electric field is? (b) In the region outside the planes the magnitude of the electric field is?

1) Two parallel flat planes of positive charge are separated by a distance d. Plane #1 hascharge density 1, and plane #2 has a charge density 2 and 1> 2.(a) In the region between the planes, the magnitude of the electric field is?(b) In the region outside the planes the magnitude of the electric field …

## If the rate of formation of ammonia is 0.345 M/s, what is the rate of disappearance of N2?

If the rate of formation of ammonia is 0.345 M/s, what is the rate of disappearance of N2? EXPERT ANSWER The balanced reaction is : N2 (g) + 3 H2 (g)  2 NH3 (g) Rate of reaction = –[N2]/t = -(1/3) *  [H2]/t = (1/2) *  [NH3]/t Given :  [NH3]/t = 0.345 M/s –[N2]/t = (1/2) *  [NH3]/t –[N2]/t = (1/2) * (0.345 M/s) …

## Two long cylinders placed 10 cm apart as shown in the Figure, the first cylinder of radius 2 cm carries a current 11 and the second one of radius 4 cm carries a current density) = cr where c = 30000 Ampere per cubic-meter. If the net magnetic field at the mid-point between the two cylinders is zero, what is the current in cylinder 12 10 cm 12 =====

EXPERT ANSWER I2 = I1 = 0.447A => 0.45A ( approximately