Velocity - 8th grade (13y) - math problems

The velocity of an object is the time rate of change of its position. Velocity is a specification of an object's speed and direction of motion (e.g. 20 m/s to the south).

In everyday use and in kinematics, the speed of an object is the magnitude of its velocity (the rate of change of its position) - scalar.

  1. Cheetah vs antelope
    motion2 When the cheetah began chasing the antelope, the distance between them was 120 meters. Although the antelope was running at 72km/h, the cheetah caught up with it in 12 seconds. What speed was the cheetah running?
  2. Cyclists and walkers
    time_1 A group of tourists started at 8:00 at speed 4 km/h walk. At half-past ten, another group started on a bike and caught up with a group of tourists at 10:50. What was the average speed of cyclists?
  3. Two cylinders
    sudy Two cylinders are there one with oil and one with an empty oil cylinder has no fixed value assume infinitely. We are pumping out the oil into an empty cylinder having radius =1 cm height=3 cm rate of pumping oil is 9 cubic centimeters per sec and we are pu
  4. Where and when
    cars The truck left Kremnica at 11:00 h at a speed of 60km/h. At 12:30 h, the passenger car started at an average speed of 80km/h. How many kilometers from Kremnica will the passenger car reach truck, and when?
  5. Positional energy
    energy What velocity in km/h must a body weighing 60 kg have for its kinetic energy to be the same as its positional energy at the height 50 m?
  6. Propeller
    Tupolev_Tu-95 The aircraft propeller rotates at an angular speed of 200 rad/s. A) What is the speed at the tip of the propeller if its distance from the axis of rotation is 1.5 m? B) What path does the aircraft travel during one revolution of the propeller at a speed
  7. The escalator
    eskalator I run up the escalator at a constant speed in the direction of the stairs and write down the number of steps A we climbed. Then we turn around and run it at the same constant speed in the opposite direction and write down the number of steps B that I climb
  8. Bike ride
    car Marek rode a bike ride. In an hour, John followed him on the same route by car, at an average speed of 72 km/h, and in 20 minutes he drove him. Will he determine the length of the way that Marek took before John caught up with him, and at what speed did Ma
  9. Between two bus stops
    bus27 Wanda lives between two bus stops at three-eighths of their distance. He started the house today and found that whether he was running to one or the other stop, he would have arrived at the bus stop. The average bus speed is 60 km/h. What is the average.
  10. RPM
    motor_rpm An electric motor makes 3,000 revolutions per minutes. How many degrees does it rotate in one second?
  11. Average speed
    truck The truck drove 1/2 of the way on the highway at 80km/h. The other half of the way 20km/h. Calculate the average speed
  12. Drive to NJ
    motion Ed drove to New Jersey at 30mph. He drove back home in 3 hours at 50 mph. How many hours did it take Ed to drive to New Jersey?
  13. Two cities
    motorbike Cities A and B are 200 km away. At 7 o'clock from city A, the car started at an average speed of 80 km/h, and from B at 45 min later the motorcycle is started at an average speed of 120 km/h. How long will they meet and at what distance from the point A it
  14. Working alone
    workers Tom and Chandri are doing household chores. Chandri can do the work twice as fast as Tom. If they work together, they can finish the work in 5 hours. How long does it take Tom working alone to do the same work?
  15. Tourist
    tourist A tourist walked an average speed of 3.5 km/h route in 6 hours. Calculate how many hours he would have passed at an average speed of 5.5 km/h.
  16. Velocipedes
    Velocipede In the 19th century, bicycles did not have a chain drive, and the pedals were connected directly to the wheel axis. This wheel diameter gradually increased until the so-called high bicycles (velocipedes) with a front wheel diameter of up to 1.5 meters, whi
  17. Two gears
    gears-3 The two gears fit together. The larger gear has 32 teeth, the smaller has 20 teeth less. How many times does turn a smaller gear if the bigger gear turns three times?
  18. Grandmother
    car_33 Mom walked out to visit her grandmother in a neighboring village 5km away and moved at a speed of 4km/h. An hour later, father drove down the same road at an average speed of 64km/h. 1) How long will take to catch mom die? 2) What is the approximate dis
  19. Wave parameters
    frequency-and-wavelength Calculate the speed of a wave if the frequency is 336 Hz and the wavelength is 10 m.
  20. Hay bags
    krav 4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?

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