# Posts by aok

Total # Posts: 24

**History**

^^

**physics**

Derek the drunk driver drives his car off the road, onto a gravel strip next to the road. Derek does not have anti-lock brakes, so his wheels lock when he enters the gravel area, and the car slides to a halt. Derek's car is traveling at a speed of 20m/s when it enters the ...

**physics**

(a) Find the pressure difference on an airplane wing where air flows over the upper surface with a speed of 126 m/s, and along the bottom surface with a speed of 101 m/s. kPa (b) If the area of the wing is 30 m2, what is the net upward force exerted on the wing? kN

**physics**

A hole in an aluminum plate has a diameter of 1.465 cm at 22.80° C. (a) What is the diameter of the hole at 199.0° C (to four significant digits)? (b) At what temperature is the diameter of the hole equal to 1.463 cm (to three significant digits)?

**physics**

(a) Find the pressure difference on an airplane wing where air flows over the upper surface with a speed of 126 m/s, and along the bottom surface with a speed of 101 m/s.(kPa) (b) If the area of the wing is 30 m2, what is the net upward force exerted on the wing? (kN)

**physics**

Suppose 560.0 J of heat is added to a 111-g piece of aluminum at 23.0° C. What is the final temperature of the aluminum?

**physics**

A water tank springs a leak. Find the speed of water emerging from the hole if the leak is 2.5 m below the surface of the water, which is open to the atmosphere.

**physics**

A horizontal pipe contains water at a pressure of 108 kPa flowing with a speed of 1.5 m/s. The pipe narrows to one-half its original diameter. What are the speed and the pressure of the water when the pipe narrows?

**physics**

A train on one track moves in the same direction as a second train on the adjacent track. The first train, which is ahead of the second train and moves with a speed of 31.3 m/s, blows a horn whose frequency is 124 Hz. If the frequency heard on the second train is 136 Hz, what ...

**PHYSICS**

A stationary horn emits a 135-Hz tone. What frequency is heard by a passenger on a train which is moving towards this horn with a speed of 31.3 m/s?

**physics**

When a 0.30-kg mass is attached to a vertical spring, the spring stretches by 15 cm. How much mass (total) must be attached to the spring to result in a 0.86-s period of oscillation?

**physics**

A 0.38-kg mass attached to a spring undergoes simple harmonic motion with a period of 0.63 s. What is the force constant of the spring?

**physics**

The position of a mass oscillating on a spring is given by x = (5.6 cm) cos [2πt / (2.03 s)]. (a) What is the period of this motion? (b) What is the first time the mass is at the position x = 0?

**physics**

A child exerts a tangential 41.9-N force on the rim of a disk-shaped merry-go-round with a radius of 2.25 m. If the merry-go-round starts at rest and acquires an angular speed of 0.086 rev/s in 3.57 s, what is its mass?

**physics**

thank you so much. i'll get working on this.

**physics**

thank you. but i don't think this is the answer they are looking for :(. hypothetically, can we assume elasticity?

**physics**

A delivery truck with a mass of 1700 kg is stopped in the street w/o its brakes on, when a small car hits it from behind. The car has a mass of 650 kg, and is traveling at 3.7m/s immediately before it hits the truck. Both the car and the truck have good bumpers, so assume the ...

**physics**

A delivery truck with a mass of 1700 kg is stopped in the street w/o its brakes on, when a small car hits it from behind. The care has a mass of 650 kg, and is traveling at 3.7m/s immediately before it hits the truck. Both the car and the truck have good bumpers, so assume the...

**physics**

After fixing a flat tire on a bicycle you give the wheel a spin. (a) If its initial angular speed was 5.41 rad/s and it rotated 13.7 revolutions before coming to rest, what was its average angular acceleration?

**physics**

A pulley rotating in the counterclockwise direction is attached to a mass suspended from a string. The mass causes the pulley's angular velocity to decrease with a constant angular acceleration α = -2.2 rad/s2. If the pulley's initial angular velocity is ω = ...

**physics**

A spot of paint on a bicycle tire moves in a circular path of radius 0.27 m. When the spot has traveled a linear distance of 2.18 m, through what angle has the tire rotated? Give your answer in radians.

**physics**

A spot of paint on a bicycle tire moves in a circular path of radius 0.27 m. When the spot has traveled a linear distance of 2.18 m, through what angle has the tire rotated? Give your answer in radians.

**physics**

To make a bounce pass, a player throws a 0.60-kg basketball toward the floor. The ball hits the floor with a speed of 6.5 m/s at an angle of 57° from the vertical. If the ball rebounds with the same speed and angle, what was the impulse delivered to it by the floor?

**physics**

A 82-kg astronaut and a 1300-kg satellite are at rest relative to the space shuttle. The astronaut pushes on the satellite, giving it a speed of 0.24 m/s directly away from the shuttle. Seven-and-a-half seconds later the astronaut comes into contact with the shuttle. What was ...