A mass of 0.20 kg , hung from a spring with a spring constant of 80.0

1.A mass of 0.20 kg, hung from a spring with a spring constant of 80.0 N/m, is set into an up-and-down simple harmonic motion. If the mass is displaced from equilibrium by 0.10 m and released from rest, what is its speed when moving through the equilibrium point? 选项： A、0 B、1.4 m/s C、2.0 m/s D、3.4 m/s

2.A mass of 0.20 kg, hung from a spring with a spring constant of 80.0 N/m, is set into an up-and-down simple harmonic motion. If the mass is displaced from equilibrium by 0.10 m and released from rest, what is its speed when moving through the equilibrium point?选项： A:0; B:1.4 m/s; C:2.0 m/s; D:3.4 m/s

3.A mass of 0.40 kg, hanging from a spring with a spring constant of 80 N/m, is set into an up-and-down simple harmonic motion. What is the speed of the mass when moving through a point at 0.05 m displacement? The starting displacement of the mass is 0.10 m from its equilibrium position.( )选项： A:zero B:1.4 m/s C:1.7 m/s D:1.2 m/s E:1.0 m/s

4.中国大学MOOC: An object of mass 0.50 kg, hanging from a spring with a spring constant of 8.0 N/m, is set into a simple harmonic motion. What is the maximum speed of the object if its maximum displacement is 0.10 m?

5.A mass on a spring vibrates in simple harmonic motion at a frequency of 4.0 Hz and an amplitude of 8.0 cm. If the mass of the object is 0.20 kg, what is the spring constant?( ) 选项：A:40 N/m B:87 N/m C:126 N/m D:160 N/m E:190 N/m

6.A mass on a spring vibrates in simple harmonic motion at a frequency of 4.0 Hz and an amplitude of 8.0 cm. If the mass of the object is 0.20 kg, what is the spring constant?( )选项： A:40 N/m B:87 N/m C:126 N/m D:160 N/m E:190 N/m

7.An object of mass 0.50 kg, hanging from a spring constant of 8.0 N/m, is set into a sample harmonic motion. What is the maximum speed of the object if its maximum displacement is 0.1m?（）选项： A、0.2 m/s B、0.4 m/s C、0.8 m/s D、1.6 m/s

8.A 0.20-kg mass is oscillating on a spring over a horizontal frictionless surface. When it is at a displacement of 2.6 cm for equilibrium it has a kinetic energy of 1.4 J and a spring potential energy of 2.2 J. What is the maximum speed of the mass during its oscillation (in m/s)? ( )选项： A:3.7 m/s B:4.7 m/s C:6.0 m/s D:6.3 m/s E:7.8 m/s

9.1) A 0.20-kg mass is oscillating on a spring over a horizontal frictionless surface. When it is at a displacement of 2.6 cm for equilibrium it has a kinetic energy of 1.4 J and a spring potential energy of 2.2 J. What is the maximum speed of the mass during its oscillation (in m/s)? 选项： A、3.7 m/s B、4.7 m/s C、6.0 m/s D、6.3 m/s E、7.8 m/s

10.A 0.20 kg object, attached to a spring with spring constant k = 10 N/m, is moving on a horizontal frictionless surface in simple harmonic motion of amplitude of 0.080 m. What is its speed at the instant when its displacement is 0.040 m? (Hint: Use conservation of energy.)( )选项： A:9.8 m/s B:4.9 m/s C:49 cm/s D:24.5 cm/s E:53 cm/s

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1) A 0.20-kg mass is oscillating on a spring over a horizontal frictionless surface. When it is at a displacement of 2.6 cm for equilibrium it has a kinetic energy of 1.4 J and a spring potential energy of 2.2 J. What is the maximum speed of the mass during its oscillation (in m/s)?

12.Suppose a 0.3-kg mass on a spring that has been compressed 0.10 m has elastic potential energy of 1.0 J. How much further must the spring be compressed to triple the elastic potential energy? ( )选项： A:0.30 m B:0.20 m C:0.17 m D:0.07 m E:0.05 m

13.Suppose a 0.3-kg mass on a spring that has been compressed 0.10 m has elastic potential energy of 1.0 J. How much further must the spring be compressed to triple the elastic potential energy? ( )选项： A:0.07 m B:0.20 m C:0.30 m D:0.17 m E:0.05 m

14.A 1.0 kg block is attached to a spring with spring constant 16 N/m and is at rest on a smooth horizontal plane. It is hit with a hammer and acquires instantaneously a speed of 0.40 m/s. The speed of the block at x = A/2 is ___________ m/s (round to two decimal places ).

15.A mass on a spring vibrates in simple harmonic motion at a frequency of 4.0 Hz and an amplitude of 8.0 cm. If a timer is started when its displacement is a maximum (hence x = 8 cm when t = 0), what is the displacement of the mass when t = 3.7 s? ( )选项： A:zero B:0.025 m C:0.036 m D:0.080 m E:0.095 m

16.A 0.20-kg mass is oscillating on a spring over a horizontalfrictionless surface. When it is at a displacement of 2.6 cm forequilibrium it has a kinetic energy of 1.4 J and a spring potentialenergy of 2.2 J. What is the maximum speed of the mass during itsoscillation (in m/s)? A: 3.7m/s B: 4.7m/s C: 6.0m/s D: 6.3m/s E: 7.8m/s

17.Two blocks with different mass are attached to either end of a light rope that passes over a light, frictionless pulley that is suspended from the ceiling. The masses are released from rest, and the more massive one starts to descend. After this block has descended 1.20 m, its speed is 3.00 m/s. If the total mass of the two blocks is 15.0 kg. The mass of the more massive block is _____(kg).(g=9.8m/s^2, round to one decimal place)

18.A mass on a spring vibrates in simple harmonic motion at a frequency of 4.0Hz and an amplitude of 8.0cm.
If a timer is started when its displacement is a maximum (hence x=8cm
when t=0),
what is the
displacement of the mass when t=3.7s? 选项： A、zero B、0.025
m C、0.036
m D、0.080
m E、0.095
m

19.A 20-g bullet moving at 1 000 m/s is fired through a one-kg block of wood emerging at a speed of 100 m/s. If the block had been originally at rest and is free to move, what is its resulting speed? 选项： A、9 m/s B、18 m/s C、90 m/s D、900 m/s E、60 m/s F、600 m/s

20.You were at rest and a police car with its siren on was passing you with a constant speed. You found that the frequencies of the siren were respectively 550 Hz and 450 Hz when the police car was moving toward and away from you. Assume that the speed of sound in air is 340 m/s. The speed of the police car was m/s.

21.At one instant, the center of mass of a system of two particles is located on the x-axis at x = 2.0 m. One of the particles is at the origin. The other particle has a mass of 0.10 kg and is at rest on the x-axis at x = 8.0 m.The mass of the particle at the origin is (kg).

22. A child with a mass of 20 kg moves at a speed of 18 km/h sat on a sledge with a mass of 5 kg. What is the total quantity of motion of the child-sledge combination? 选项： A:125 kg · m/s B: 100 N C:450 kg · m/s D:450 N E:360 kg · m/s

23.The motion of a piston in an automobile engine is nearly simple harmonic. If the 1-kg piston travels back and forth over a total distance of 10.0 cm, what is its maximum speed when the engine is running at 3 000 rpm?( ) 选项： A、3.93 m/s B、15.7 m/s C、7.85 m/s D、31.4 m/s E、1.66 m/s