Julie drives 100 mi to Grandmother's house. On the way to Grandmother's, Julie drives half the distance at 50.0mph and half the distance at 67.0mph . On her return trip, she drives half the time at 50.0mph and half the time at 67.0mph .
What is her average speed on the return trip?
I crunched up one of my rims pretty badly today, there's a picture below. I'm hoping it can be repaired without having to get a new rim entirely. Are these repairable and about how much would it cost to be repaired.2 AnswersMaintenance & Repairs8 years ago
I crunched up one of my rims pretty badly today. I'm hoping it can be repaired without having to get a new rim entirely. Whats the most expensive it would be and how much damage can be repaired without having to buy a new rim? The rims I have now are about $1,000 each.6 AnswersMaintenance & Repairs8 years ago
A projectile is shot directly away from Earth's surface. Neglect the rotation of Earth.
(a) As a multiple of Earth's radius RE, what is the radial distance a projectile reaches if its initial speed is two-thirds of the escape speed from Earth?
(b) As a multiple of Earth's radius RE, what is the radial distance a projectile reaches if its initial kinetic energy is three-fifths of the kinetic energy required to escape Earth?2 AnswersPhysics8 years ago
A 20 kg satellite has a circular orbit with a period of 2.2 h and a radius of 7.4X10^6 m around a planet of unknown mass. If the magnitude of the gravitational acceleration on the surface of the planet is 7.2 m/s2, what is the radius of the planet?2 AnswersPhysics8 years ago
The function x = (2.5 m) cos[(6π rad/s)t + π/6 rad] gives the simple harmonic motion of a body. Find the following values at t = 4.0 s.
(a) the displacement
(b) the velocity
(c) the acceleration
(d) the phase of the motion
e) the frequency of the motion
(f) the period of the motion
In the figure below, a square of edge length 20.0 cm is formed by four spheres of masses m1 = 6.00 g, m2 = 4.00 g, m3 = 1.00 g, and m4 = 6.00 g. In unit-vector notation, what is the net gravitational force from them on a central sphere with mass m5 = 2.00 g?
In the figure below, a 58.0 kg uniform square sign, of edge L = 2.00 m, is hung from a horizontal rod of length dh = 3.00 m and negligible mass. A cable is attached to the end of the rod and to a point on the wall at distance dv = 4.00 m above the point where the rod is hinged to the wall.
(a) What is the tension in the cable?
(b) What are the magnitude and direction of the horizontal component of the force on the rod from the wall? (Include the sign. Take the positive direction to be to the right.)
(c) What are the magnitude and direction of the vertical component of this force? (Include the sign. Take the positive direction to be upward.)
A horizontal vinyl record of radius 0.13 m rotates about a vertical axis through its center with an angular speed of 4.7 rad/s. The rotational inertia of the record about its axis of rotation is 5.0 10-4 kg·m2. A wad of putty of mass 0.050 kg drops vertically onto the record from above and sticks to the edge of the record. What is the angular speed of the record immediately after the putty sticks to it?
The following gives the angular momentum (t) of a particle in four situations:
(1) l = 3t + 4
(2) l = -6t2
(3) l = 2
(4) l = 4/t
(a) In which situation is the net torque on the particle zero?
(b) In which situation is the net torque on the particle positive and constant?
(c) In which situation is the net torque on the particle negative and increasing in magnitude (t > 0)?
(d) In which situation is the net torque on the particle negative and decreasing in magnitude (t > 0)?