Unit conversion - 9th grade (14y) - math problems

Number of problems found: 305

  • Colorado
    Colorado The state Colorado has the shape of a rectangle. The map is sold on 2 posters. The first has dimensions of 70 cm and 50 cm in a scale of 1: 1,000,000. The second poster has dimensions of 175 cm and 125 cm. What is the scale of the second poster?
  • There
    watertank There is water in the block-shaped tank with dimensions of 3 m 1.5 m 5 m, it occupies 70% of the tank volume. Find the volume of water in the tank (in hl) .
  • A diesel car
    fuel A diesel car costs $2599 more than an unleaded petrol car and travels an average of 25,000km per year. Diesel petrol has a consumption rate of 7.4L per 100km and costs $1.39 per litre. Unleaded petrol has a consumption rate of 8.5L per 100km and costs $1.
  • Dynamometer
    archimedes2 What is the volume of a body that stretches a dynamometer in air, on which it is suspended by a force of 2.5 N, and if it is immersed in alcohol with a density of 800 kg/m ^ 3, does it tension the dynamometer with a force of 1.3 N?
  • Above water surface
    archimedes If we remove the stone from the water, we apply a force of 120N. How much force will we have to exert if we move the stone above the water surface? The density of the stone is 5000 kg/m ^ 3.
  • What power
    radiator What power should the radiator have in a room 5x4 meters with a height of 3 meters? Hint: Calculate 35 watts per meter ^ 3 in case you need 22 degrees in the room but you need about 24 degrees in the bathroom. It's an old heating cheat, but it will defini
  • Two cars
    cars Two cars (trucks and passenger) drove simultaneously from two places 50 km away. If they go against each other, they will meet in 30 minutes. If they follow each other in the same direction, the car will catch up with the truck in 2.5 hours. What is the s
  • Thermometer
    energy Immerse a thermometer with a heat capacity of 2.0 J. K-1 in water weighing 67.0 grams. Before immersion in water, the thermometer showed a temperature of 17.8 degrees Celsius. After reaching equilibrium, the temperature is 32.4 degrees. What was the water
  • Latent heat
    ice How much heat is needed to take from 100 g of water at 20°C to cool to ice at -18°C? Mass heat capacity c (ice) = 21kJ/kg / °C; c (water) = 4.19 KJ/kg / °C and the mass group heat of solidification of water is l = 334kJ/kg
  • The volleyball ball
    volejball The volleyball ball can have a circumference after inflation of at least 650 max 750 mm. What volume of air can this ball hold, if its circumference is the average of the minimum and maximum inflation of the ball.
  • Heat transfer
    sphere_Nickel We placed a lead object weighing 0.4 kg and 250°C in 0.4 L water. What was the initial temperature of water t2 if the object's temperature and the water after reaching equilibrium was 35°C? We assume that the heat exchange occurred only between the lead o
  • Decelleration
    car In a braking test, a vehicle that travels at 51 km/h stops in 5 s. What is the acceleration?
  • Per shift
    time Two cars take beets from the same field to the sugar factory. Both drive at the same average speed. A car with mechanical tipping needs 15 minutes to travel to the sugar factory and back. A car that does not have a mechanical tipping needs 6 minutes longe
  • The square
    woord The square oak board (with density ρ = 700 kg/m3) has a side length of 50 cm and a thickness of 30 mm. 4 holes with a diameter of 40 mm are drilled into the board. What is the weight of the board?
  • Diagonals of a prism
    space_diagonal The base of the square prism is a rectangle with dimensions of 3 dm and 4 dm. The height of the prism is 1 m. Find out the angle between the body diagonal with the diagonal of the base.
  • Long hot dog
    parky In Kostelec above Black Forest, they made a record-long hot dog. When slowly moved it to the square, one of the spectators decided to measure its length: the size of his footprint is 28 cm; he measured 20 feet in travel direction, counted 5 feet against t
  • Triangular prism
    hranol3b The regular triangular prism has a base edge of 8.6 dm and a height of 1.5 m. Finf its volume and surface area.
  • The resistance
    resistor What is the resistance of an aluminum wire 0.2 km long and 10 mm in diameter?
  • Duo mix
    chicken In one kilogram of meat of two colors is 650 g of pork, the rest is chicken. One kilogram of pork is 40 CZK more expensive than a kilogram of chicken. How many CZK cost one kilogram of chicken meat so that the price of one kilogram of meat of two colors i
  • Motorbike circuit
    motorbike2 On a 2,550 m long circuit, two motorcycles go at such speeds that they meet every minute if they go against each other and run every 5 minutes if they go in the same direction. Find their speeds.

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Unit conversion - math problems. Examples for 9th grade.