# ATT

Popular questions and responses by ATT
1. ## physics

If the resultant force acting on a 2kg object is equal to (3i+4j)N, what is the change in kinetic energy as the object moves from (7i-8j)m to (11i-5j)m?

2. ## physics

A 4kg block is lowered down a 37° incline a distance of 5m from point A to point B. A horizontal force (F = 10 N) is applied to the block between A and B as shown in the figure. The kinetic energy of the block at A is 10 J and at B it is 20 J. How much

3. ## physics

As a 2.0-kg object moves from (2i+5j)m to (6i-2j)m, the constant resultant force acting on it is equal to (4i-3j)N. If the speed of the object at the initial position is 4.0 m/s, what is its kinetic energy at its final position? Ans: 40J

4. ## physics

A rocket engine consumes 450 kg of fuel per minute. If the exhaust speed of the ejected fuel is 5.2 km/s, what is the thrust of the rocket?

5. ## physics

A car travels around an unbanked highway curve (radius 0.15 km) at a constant speed of 25 m/s. What is the magnitude of the resultant force acting on the driver, who weighs 0.8kN?

6. ## physics

A bead slides without friction around a loop-the-loop. The bead is released from a height h = 3.5R. A is at the highest point of the loop and R is the radius of the loop (a) What is its speed at point A? (b) How large is the normal force on it if its mass

7. ## physics

At an instant when a particle of mass 80 g has a velocity of 25 m/s in the positive y direction, a 75g particle has a velocity of 20 m/s in the positive x direction. What is the speed of the center of mass of this two-particle system at this instant?

8. ## physics

At the instant a 2.0-kg particle has a velocity of 4.0 m/s in the positive x direction, a 3.0-kg particle has a velocity of 5.0 m/s in the positive y direction. What is the speed of the center of mass of the two-particle system?

9. ## physics

A 3kg mass sliding on a frictionless surface has a velocity of 5m/s east when it undergoes a one-dimensional inelastic collision with a 2kg mass that has an initial velocity of 2m/s west. After the collision the 3kg mass has a velocity of 1m/s east. How

10. ## physics

Two blocks connected by a cord passing over a small, frictionless pulley rest on frictionless planes: a) What is the acceleration of the blocks? b) What is the tension in the cord? c) Which way will the system move when the blocks are released from rest?

11. ## physics

What is the gravitational force on a 20Kg satellite circling the earth (Re = 6.4 x 10^6 m, Me = 6 x 10^24Kg) with a period of 5hr?

12. ## physics

As in the figure below, a simple harmonic oscillator is attached to a rope of linear mass density 5.4 ✕ 10^−2 kg/m, creating a standing transverse wave. There is a 3.2-kg block hanging from the other end of the rope over a pulley. The oscillator has an

13. ## physics

The figure below shows a cubical box that has been constructed from uniform metal plate of negligible thickness. The box is open at the top and has edge length L = 39 cm. (a) Find the x coordinate of the center of mass of the box. (b) Find the y coordinate

14. ## physics

A 6 kg mass is attached to a light cord that passes over a massless, frictionless pulley. The other end of the cord is attached to a 3.5 kg mass as in Figure below. Use conservation of energy to determine the final speed of the 6kg mass after it has fallen

15. ## physics

A skier slides down a hill starting with zero velocity at a height of h1 = 45.2 m above the bottom of the hill. The shape of the terrain is like a cosine wave. a) What is the velocity of the skier on top of the second, intermediate hill, whose height is h2

16. ## physics

While a boat is being towed at a speed of 11m/s, the tension in the towline is 9.5kN. What is the power supplied to the boat through the towline?

17. ## physics

A force given by F(x) = 4x^3 x̂ (in N/m^3) acts on a 1kg mass moving on a frictionless surface. The mass moves from x = 4 m to x = 7 m. (a) How much work is done by the force? (b) If the mass has a speed of 1 m/s at x = 4 m, what is its speed at x = 7 m?

18. ## physics

A constant force, F = (4.39, −3.79, 2.02) N, acts on an object of mass 19.5 kg, causing a displacement of that object by r = (4.02, 3.68, −2.45) m. What is the total work done by this force?

19. ## physics

A boy on board a cruise ship drops a 30g marble into the ocean. If the resistive force proportionality constant is 0.5kg/s, what is the terminal speed of the marble in m/s?