BackAndrea dangles her watch from a thin piece of string while the jetliner she is in accelerates for takeoff, which takes about 21 s. Estimate the takeoff speed of the aircraft if the string makes an angle of 24° with respect to the vertical, Fig. 4–61.
A man pushes on a piano with mass kg; it slides at constant velocity down a ramp that is inclined at above the horizontal floor. Neglect any friction acting on the piano. Calculate the magnitude of the force applied by the man if he pushes parallel to the floor.
An 85,000 kg stunt plane performs a loop-the-loop, flying in a 260-m-diameter vertical circle. At the point where the plane is flying straight down, its speed is 55 m/s and it is speeding up at a rate of 12 m/s per second. What angle does the net force make with the horizontal? Let an angle above horizontal be positive and an angle below horizontal be negative.
A particle of mass m moving along the x-axis experiences the net force Fₓ = ct, where c is a constant. The particle has velocity v₀ₓ at t = 0. Find an algebraic expression for the particle's velocity vₓ at a later time t.
A 2.0 kg object initially at rest at the origin is subjected to the time-varying force shown in FIGURE P6.38. What is the object's velocity at t = 4 s?
The position of a 2.0 kg mass is given by x = (2t3 - 3t2) where t is in seconds. What is the net horizontal force on the mass at t = 1s?
A 2.0 kg projectile with initial velocity v = 8.0 î m/s experiences the variable force F = -2.0t î + 4.0t² ĵ N, where t is in s. What is the projectile's speed at t = 2.0 s?
A -kg crate is suspended from the end of a short vertical rope of negligible mass. An upward force is applied to the end of the rope, and the height of the crate above its initial position is given by ( m/s)t + ( m/s3)t3. What is the magnitude of when s?