Molecular Physics | Thermodynamics Answers

Determine the net heat transfer through the black body disc with radius 4cm and mass 9g, at 32⁰C when transferred to a surrounding temperature of 65⁰C.

‏Its hunting season and Natalia wants part of the action so she grabs her Nerf gun and fires a 2 gram foam dart [ W 42 ° N ] into the air with a velocity of 24m / s . A goose , travelling at 5m / s [ W ] gets pegged and it isn't impressed , so it drops a payload of goose poop on Natalia's shiny Mercedes convertible . ( Yup ... the top was down ) What height did the Nerf dart reach ? ( Assume Natalia stands 1.6m tall ) How long does it take for the goose's payload to hit the Mercedes ? ( Assume the Mercedes is 1.6m tall )

(a) Find the magnitude of the gravitational force (in N) between a planet with mass 8.25 ✕ 10²⁴ kg and its moon, with mass 2.30 ✕ 10²² kg, if the average distance between their centers is 2.30 ✕ 10⁸ m.

__N

(b) What is the moon's acceleration (in m/s²) toward the planet? (Enter the magnitude.)

__ m/s²

(c)

What is the planet's acceleration (in m/s²) toward the moon? (Enter the magnitude.)

__ m/s²

A bicycle tire is spinning counterclockwise at 2.60 rad/s. During a time period Δt = 1.75 s, the tire is stopped and spun in the opposite (clockwise) direction, also at 2.60 rad/s. Calculate the change in the tire's angular velocity Δ𝜔 and the tire's average angular acceleration 𝛼_av. (Indicate the direction with the signs of your answers.)

(a) the change in the tire's angular velocity Δ𝜔 (in rad/s)

__ rad/s

(b) the tire's average angular acceleration 𝛼_av (in rad/s²)

__ rad/s²

An airplane passenger has 100 cm

3

of air in his stomach just before the plane takes off sea

-

level airport. What volume will the air have at cruising altitude if cabin pressure drops to

7.50 x 10

4

Pa?

The following molecules have polar covalent bonds except

A 38.0-kg child swings in a swing supported by two chains, each 2.90 m long. The tension in each chain at the lowest point is 436 N.

(a) Find the child's speed at the lowest point.

__ m/s

(b) Find the force exerted by the seat on the child at the lowest point. (Ignore the mass of the seat.)

__ N (upward)

A sample of blood is placed in a centrifuge of radius 16.0 cm. The mass of a red blood cell is 3.0 ✕ 10⁻¹⁶ kg, and the magnitude of the force acting on it as it settles out of the plasma is 4.0 ✕ 10⁻¹¹ N. At how many revolutions per second should the centrifuge be operated?

__rev/s

(a) Find the magnitude of the gravitational force (in N) between a planet with mass 8.25 ✕ 10²⁴ kg and its moon, with mass 2.30 ✕ 10²² kg, if the average distance between their centers is 2.30 ✕ 10⁸ m.

 __N

(b) What is the moon's acceleration (in m/s²) toward the planet? (Enter the magnitude.)

 __m/s²

(c) What is the planet's acceleration (in m/s²) toward the moon? (Enter the magnitude.)

__ m/s²