Mass - 7th grade (12y) - math problems

Mass is a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies. The basic SI unit of mass is the kilogram (kg). Other are gram, tonne, milligram, etc.

Number of examples found: 150

  • Pound2kilos
    vaha_19 How many pounds make 1 kilograms?
  • Wood
    wood_timber Wood density is 0.6 g/cm3. How many kilograms weight 1 m3 of wood?
  • Liter of gold
    zlatovlaska_1 What weight does 1 dm3 of gold have? Gold density is 19,300 kg / m3
  • Milo lifted
    vaha2_3 Milo lifted 65 lb 6 times and Jeremy lifted 50 lb 9 times. Which one lifted the most weight?
  • A jewelry
    gold A jewelry store has 20 grams of gold. If a pair of earrings need 1/4 gram of gold, how many grams are not used?
  • Barrel with liquid
    barrel Barrel with grain weight 297 kg. When it shed 48% of grain, ha weight 174 kg. What is the weight of empty barrel?
  • Gasoline
    fuel_pump2_1 How many liters of gas is in the tank if its weight 15.4kg. Specific density of gasoline is 770kg/m3.
  • Weightlifter
    culturist Weightlifter lifted 75% of its weight. Determine how much weight lifted when he weighs 132 kg.
  • Cargo
    tractor_lorry Car with cargo weight 7610 kg. Weight of car is 23% of the total weight of car and cargo. How heavy is cargo?
  • Mushrooms
    huby Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
  • Oak cuboid
    hranol4sreg_3 Oak timber is rectangular shaped with dimensions of 2m, 30 cm and 15 cm. It weight is 70 kg. Calculate the weight 1 dm³ of timber.
  • Fe vs. H2O
    atoms_Fe The volume of what the body of the same weight is greater - iron or water?
  • Wood prisms
    wood How many weight 25 prisms with dimensions 8x8x200 cm? 1 cubic meter of wood weighs 800 kg.
  • Balance
    balance_weight The rod are 1.9 m long hanging weights 4 kg and 1 kg on ends. Where are centre of rod (distance from weight 4 kg) to be in balance?
  • Density - simple example
    mercury Material of density of 532 kg/m3 occupies a container volume of 79 cm3. What is its mass?
  • Excavator
    pisek The excavator bucket capacity is 0.5 m3. Determine the mass of sand that the excavator picks up. The sand density is 1650 kg/m3.
  • Weight of air
    weighting What is the weight of air in the living room measuring width 10 m length 3 m and height 3.3 m? Air density is ρ = 1.2 kg/m3.
  • Metal pyramid
    jehlan_5 Find the weight of a regular quadrilateral pyramid with a 5 cm length and 6,5 cm body height is made from material with density g/cm3.
  • Potatoes
    brambory Potatoes contain 78.6% starch. How many potatoes need to obtain 27 kg of starch?
  • Container with water
    water_2 The weight of a container with water is 2.48 kg. If the cast 75% water, the container with water has a weight of 0.98 kg. Determine the weight of the empty container. How much water was originally in the container?

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