A Particle movies along the x-axis according to the expression x(t)=-4t+2t2, the instantaneous velocity of the particle at t=3 second is
A: 8
B: 9
C: 4
D: 6
发布时间：2024-04-24 19:11:52
请在 下方输入 要搜索的题目：
A Particle movies along the x-axis according to the expression x(t)=-4t+2t2, the instantaneous velocity of the particle at t=3 second is
推荐参考答案 (
由 搜题小帮手 官方老师解答 )
答案：
以下文字与答案无关
提示：有些试题内容 显示不完整,文字错误 或者 答案显示错误等问题，这是由于我们在扫描录入过程中 机器识别错误导致,人工逐条矫正总有遗漏，所以恳请 广大网友理解。
相关试题
- 1.A Particle movies along the x-axis according to the expression x(t)=-4t+2t2, the instantaneous velocity of the particle at t=3 second is 选项： A、8 B、9 C、4 D、6
- 2.A particle is moving straight along the x direction, and its position is determined by the equation , where the unit of x is meter, and the unit of t is second. Then its velocity is expressed as （ ）选项： A:v=20t B:v=20t+8 C:v=10t D:v=10t+8
- 3.The velocity of a particle moving according to the expression v=40-5t2, the acceleration at t=2s is 选项： A、-20 B、20 C、10 D、-10
- 4.There is one particle A at origin (0,0,0), and another particle B at (1,0,0). A beam of gravitational wave propagate along z axis, and the amplitude of this gravitational wave is 0.8. Which of the following statements are correct?（ ）。选项： A:The x coordinate of particle B oscillates between 0.2 and 1.8. B:The coordinate of both particle A and particle B are unchanged. C:The distance between particle A and particle B oscillates between 0.2 and 1.8. D:We don't know the amplitude of distance oscillation between particle A and particle
- 5.According to Newton’s first law, in which of the following motions, the net force acting on the particle is zero. （ ）。选项： A:The particle is at rest B:The particle moves with a constant velocity C:The particle moves with a constant speed D:The particle moves with a constant acceleration
- 6.There is one particle A at origin (0,0,0), and another particle B at (0,0,1). A beam of gravitational wave propagate along z axis, and the amplitude of this gravitational wave is 0.8. Which of the following statements are correct?（ ）。选项： A:The x coordinate of particle B oscillates between 0.2 and 1.8. B:The coordinate of both particle A and particle B are unchanged. C:The distance between particle A and particle B oscillates between 0.2 and 1.8. D:We don't know the amplitude of distance oscillation between particle A and particle
- 7. A particle on a spring moves back and forth in simple harmonic motion along the x-axis between x1=100 cm and x2= 140 cm. The position where the particle has its maximum kinetic energy is x0 = ______________ .选项： A:100 cm; B:140 cm; C:40 cm; D:120 cm
- 8.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).
- 9.A charged particle is moving in a constant magnetic field. Assume that the magnetic field is not parallel or antiparallel to the velocity. Concerning the magnetic force exerted on the particle, which of the following statements is false?选项： A:It does no work on the particle.; B:It may increase the speed of the particle.; C:It may change the velocity of the particle.; D:It can act only on the particle while the particle is in motion.
- 10.__________ we are calculating is the instantaneous acceleration of the particle.? What|That|Which|/
- 11.题目8__________ we are calculating is the instantaneous acceleration of the particle.A. WhatB. ThatC. WhichD. /
- 12.中国大学MOOC: __________ we are calculating is the instantaneous acceleration of the particle.
- 13.A magnetic field exerts a non-zero force on a particle. Which of the following must be true? ( ) 选项： A、The particle is negatively charged. B、The particle is stationary. C、The direction of the force is perpendicular to both the velocity of the particle and the magnetic field. D、The direction of the force is parallel to the magnetic field but perpendicular to the motion of the particle. E、The direction of the force is perpendicular to the magnetic field but parallel to the motion of the particle.
- 14.What we are calculating is the instantaneous acceleration(瞬间加速度) of the particle(质点).
- 15.__________ we are calculating is the instantaneous acceleration of the particle. A. What B. That C. Which D. /
- 16.In Figure below, particle A moves along the line y= 30 m with a constant velocity of magnitude 3.0 m/s and parallel to the x axis. At the instant particle 选项：A、passes the y axis, particleB、leaves the origin with a zero initial speed and a constant acceleration of magnitude 0.40 m/s2.What angle between and the positive direction of the y axis would result in a collision?A. B.C、D、
- 17.中国大学MOOC: __________ we are calculating is the instantaneous acceleration of the particle. 参考答案
- 18. A traveling wave is propagating in an elastic medium and at time t the particle at position P has the maximum displacement. The potential energy of the particle at position P is ___________ (filling in “maximum”, “minimum”, or “zero”).
- 19.A particle with electric charge is fired into a region of space where the electric field is zero. It moves in a straight line. Can you conclude that the magnetic field in that region is zero?( )选项： A:No; an observation of an object with electric charge gives no information about a magnetic field. B:Yes, you can. C:No; the field might be parallel to the particle’s velocity. D:No; the field might be perpendicular to the particle’s velocity. E:No; the particle might need to have charge of the opposite sign to have a force exerted on it.
- 20.A particle with electric charge is fired into a region of space where the electric field is zero. It moves in a straight line. Can you conclude that the magnetic field in that region is zero?( )选项： A:Yes, you can. B:No; the field might be perpendicular to the particle’s velocity. C:No; the field might be parallel to the particle’s velocity. D:No; the particle might need to have charge of the opposite sign to have a force exerted on it. E:No; an observation of an object with electric charge gives no information about a magnetic field.
- 21.1. A charged particle is traveling through a uniform magnetic field. Which of the following statements are true of the magnetic field? 选项： A、It exerts a force on the particle parallel to the field. B、It exerts a force on the particle along the direction of its motion. C、It increases the kinetic energy of the particle. D、It exerts a force that is perpendicular to the direction of motion.
- 22.有以下程序：#include void main(){ int c[10]={1,2,3,4,5,6,7,8,9,0},i,t; for(i=0;i { t=c[i]; c[i]=c[i+1]; c[i+1]=t; } for(i=0;i printf("%d,",c[i]);}程序运行后的输出结果是__________。选项： A:1,2,3,4,5,6,7,8,9,0, B:2,1,4,3,6,5,8,7,0,9, C:0,9,8,7,6,5,4,3,2,1, D:0,1,2,3,4,5,6,7,8,9,
-
23.A particle with electric
charge is fired into a region of space where the electric
field is zero. It moves in a straight line. Can you conclude that the
magnetic field in that region is zero?() 选项： A、Yes,
you can. B、No;
the field might be perpendicular to the particle’s velocity. C、No;
the field might be parallel to the particle’s velocity. D、No;
the particle might need to have charge of the opposite sign
to have a force exerted on it. E、No;
an observation of an object with electric
charge gives no information about a magnetic
field.
