[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fk45uDlTX1DRz59Sxzhk_MAXoYvAprjDNBNuiAe9b3WE":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":10,"question":17,"related":18,"source":28,"type":29},[],"2025-03-25 15:18:07",180257845,[8,9],"√","×",{"count":11,"courseId":12,"courseImg":13,"courseName":14,"workId":15,"workName":16},17,"c3c8a3c774ccaf53e538ec1fe9053d11","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F060ff84879b2f623ef505233bbac89d7.png","Physical Modelling A","work_42130649","质点动力学作业","If there is an elastic collision between two objects, their total kinetic energy will not change",[19,30,39,48,53,58,63,68,73,76],{"answer":20,"createTime":5,"id":21,"options":22,"question":27,"source":28,"type":29},[],180257829,[23,24,25,26],"870","87","8700","8.7","A 1500-kg car moving at 20m\u002Fs crosses the rounded top of a hill (treat as an arc of circle, radius 100m). What is the normal force N acted by the hill? (g=9.80m\u002Fs^2) N = _________ N","v1",0,{"answer":31,"createTime":5,"id":32,"options":33,"question":38,"source":28,"type":29},[],180257831,[34,35,36,37],"10","7.3","12.6","73","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F95a45cc8d5d34ac08808120bdd8060cf.png\"> \u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F8296f722c90c33ed8724c0dbd0f33483.png\">",{"answer":40,"createTime":5,"id":41,"options":42,"question":47,"source":28,"type":29},[],180257833,[43,44,45,46],"\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F0be7dce1b91779b467ccbd8fc2e25bd9.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F62973bf50b92d924f8ce8a0aae16d4d4.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F69c57944ba8f3a4e7a71333e03f037be.png\">","\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F09a8449ab755f272aa481badb8eebc3a.png\">","A conical pendulum composed of a massless rope (length L) and a bob (mass m) is shown in Figure. How much is the period for the pendulum? \u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fcbe8587bb6d92d5b4a8e3eac8429760e.png\">",{"answer":49,"createTime":5,"id":50,"options":51,"question":52,"source":28,"type":29},[],180257835,[8,9],"Newton's laws can be used in any reference frame",{"answer":54,"createTime":5,"id":55,"options":56,"question":57,"source":28,"type":29},[],180257837,[8,9],"The kinetic energy of an object depends on the reference frame in which its motion is measured",{"answer":59,"createTime":5,"id":60,"options":61,"question":62,"source":28,"type":29},[],180257839,[8,9],"A force acting on an object does no work on it, if the force is always perpendicular to the moving direction of object",{"answer":64,"createTime":5,"id":65,"options":66,"question":67,"source":28,"type":29},[],180257841,[8,9],"Only nonconservative forces can change the kinetic energy of an object",{"answer":69,"createTime":5,"id":70,"options":71,"question":72,"source":28,"type":29},[],180257843,[8,9],"The total momentum of a system remains constant in any case",{"answer":74,"createTime":5,"id":6,"options":75,"question":17,"source":28,"type":29},[],[8,9],{"answer":77,"createTime":5,"id":78,"options":79,"question":84,"source":28,"type":29},[],180257847,[80,81,82,83],"The linear momentum of the cart is conserved","The linear momentum of the particle is conserved","The linear momentum of the cart and linear momentum of the particle are both conserved","The linear momentum of the cart and linear momentum of the particle are both not conserved","A particle is suspended from a post on top of a cart by a light string as shown in Figure. The cart and particle are initially moving to the right at constant speed v, with the string vertical. The cart suddenly comes to rest when it runs into and sticks to a bumper. Which of the following statements is true about the collision process? \u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fbd23acc8e612ec2412ac09d498140191.png\">"]