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# Download Topic-2---Vectors-and-Forces

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Edexcel (9-1) Triple Physics Topic 2 Retrieval Practice Challenge Calculate the final speed of a car at rest of mass 1000kg that is hit Explain why doubling the velocity Calculate the acceleration of a by a lorry of mass 7500kg of an object would quadruple the bike that changes speed from 10 travelling at 20 m/s which then stopping distance. m/s to rest in 0.4 seconds. comes to a rest. Define momentum. Describe how to calculate the velocity from a distance time graph. Explain the difference between vector and scalar quantities. Describe the relationship Describe and explain what would Calculate the speed of a car that between the weight of an object happen to a bag in a car that moves 1500m in 1 minute. and the gravitational field braked suddenly without being strength. secured. Calculate the weight of a 250g mass on Earth. One Point List two factors that can increase the reaction time of the driver of a car. Two Points Three Points Recall an example of a vector and scalar pair. Four Points Edexcel (9-1) Triple Physics Topic 2 Answers Momentum before = momentum The kinetic energy is related to after (1) the work done to stop the vehicle Before = p = m x v (1) (1), the kinetic energy is the = 7500 x 5 = 37500 kgm/s (1) square of the velocity (1), double After: 150000 = 1000 x v the velocity then quadruple the v= 37.5 m/s (1) work (1). a = (v-u) / t (1) = (0-10)/0.4 (1) =-25 m/s2 (1) The velocity can be calculated from the gradient of a distance time graph (1). Vector quantities have both magnitude (size) and direction, whereas scalar quantities have only magnitude. v = x/t t = 1 x 60 = 60 s (1) = 1500 / 60 (1) = 25 m/s (1) The greater the field strength then the greater the weight (1) as W = m x g (1). Bag has a momentum (1), when the car breaks the bag would continue to travel in a straight line (1) at the same velocity (1) until it collides with the car again to be decelerated (1). W= mxg m = 250 / 1000 = 0.25 kg (1) W = 0.25 x 10 (1) W = 2.5 N (1) Drugs (1), Tiredness (1), Distractions (1), Alcohol (1). Velocity, Speed (1) or Displacement, Distance (1) p = m x v (1)