Velocity - 7th grade (12y) - 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. Magnitude of angle
    clocks What magnitude has an obtuse angle enclosed by the hands of clocks at 12:20 hours?
  2. Rate 3
    time_1 A liquid is heated at a rate of 5 degrees Celsius per minute. If the temperature now is at 39 degrees Celsius, after how long will the temperature be 94 degrees Celsius?
  3. Average speed
    cyklo The average speed of a pedestrian who walked 10 km was 5km/h, the average speed of a cyclist on the same track was 20km/h. In how many minutes did the route take more than a cyclist? Q
  4. Two trains
    trains Two trains departed from City A and City B against each other. They met after some time. The first train then took 9 hours to reach city B, and the second train took 4 hours to reach city A. In what proportion were the train speeds?
  5. Equal temperature
    city The temperatures of the two cities were measured at the same time. The temperature in city A was 60 degrees And rose at a constant rate of 2 degrees per hour. The temperature in city B was 40° and rose at a constant rate of 10° per hour Enter the tim
  6. A filter
    bazen It is a pool with a volume of 3500 liters. The filter filters at 4m cubic per hour. How many minutes would it filter the entire pool?
  7. Two ships
    ship Two ships sailed from Venice - a cargo speed of 10 knots and a ferry speed of 18 knots. At what time will the ferry catch up with the cargo ship if it sailed 10 hours later?
  8. 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?
  9. 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?
  10. Car loop
    preteky The toy car runs at an average speed of 2 m/s. In a minute, it will pass the entire circuit five times. How long is the loop?
  11. RPM
    motor_rpm An electric motor makes 3,000 revolutions per minutes. How many degrees does it rotate in one second?
  12. 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.
  13. 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, wh
  14. Constant motion
    car_36 The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
  15. Round-trip
    car_35 A woman works at a law firm in city A which is about 50 miles from city B. She must go to the law library in city B to get a document. Find how long it takes her to drive​ round-trip if she averages 40 mph.
  16. 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?
  17. Hay bags
    krav 4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?
  18. The cyclist
    cyclist_38 The cyclist drove from A to B, 60 km away. The first half drove at 30km/h, the second at 20km/h. How long did it take for him?
  19. Two vans
     two vans At 8:30 a. M. , two vans leave at a parking area. They travel in opposite directions: one van travels at 48 km/h and the other at 62 km/h. At what time will the cars be 550 km apart?
  20. Walking
    tourist_5 Lucie can walk about 3 4/5 miles each hour. How far can she walk in 2 hours 45 minutes?

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Do you want to convert velocity (speed) units? See also more information on Wikipedia.