Two boys

Two boys weighing 60kg and 90kg move on roller skates and are attracted to each other by a rope. One boy exerts a force of 15N. What force does the other boy exert? What accelerations will the boys gain? Do not consider friction or air resistance.

Correct answer:

F₂ =  15 N
a₁ =  0.25 m/s²
a₂ =  0.1667 m/s²

Step-by-step explanation:

$$\begin{gathered} F_1=15\text{ N } \\ {m}_1=60\text{ kg } \\ {m}_2=90\text{ kg } \\ {F}_2=F_1=15\text{ N} \end{gathered}$$

$$\begin{gathered} F_1=m_1{a}_1 \\ {a}_1=F_1\mathrm{/}{m}_1=15\mathrm{/}60=0.25{\text{m/s}}^2 \end{gathered}$$

$$\begin{gathered} F_2=m_2{a}_2 \\ {a}_2=F_2\mathrm{/}{m}_2=15\mathrm{/}90=0.1667{\text{m/s}}^2 \end{gathered}$$

Try another example

Related math problems and questions:

• Chained winch
  When digging a well, a chained winch is used to balance the material. An empty shackle weighs 8 kg, a full 64 kg. What force must the worker exert on the crank handle when pulling the shackle with a uniform movement from a depth of 5 m if the shaft diamet
• Forces on earth directions
  A force of 60 N [North] and 80 N [East] is exerted on an object wigth 10 kg. What is the acceleration of the object?
• Inclined plane
  1. How much work W we have to do to pull a body weighing 200 kg along an inclined plane with a length of 4 m to a total height of 1.5 m. 2. Find the force we need to exert to do this if we neglect frictional resistance. 3. Find the force we would need if
• A stone
  There is a stone weighing 60 kg on the billet. The distance from the support point to the stone is 20cm. The length of the billet is 1m. Determine the force exerted by the hand at the end of the billet.
• Tarzan
  Tarzan, weighing m = 90 kg, tries to cross the river by swinging with a vine hanging from a tree leaning over the river. Liana has a length l = 12 m. The speed of the Tarzan in the lowest swing position is v = 8 m/s. Tarzan doesn't know that the liana wil
• Same force
  The trunk of 5m length and 95 kilograms has a center of gravity 2m from the thicker end. The tribe is carried by two men, one at the thicker end. At what distance does the trunk carry a man from the other end to make the same force on it?
• Trio weight
  Adelka, Barunka, and Cecilka are weight in pairs. Adelka with Barunka weighs 98 kg, Barunka with Cecilka 90 kg and Adelka with Cecilka 92 kg. How much does each of them weigh?
• Dynamometer
  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?
• The elevator
  The elevator car weighing 400 kg rises from the third to the fifth floor. By what value will the potential gravitational energy of the cabin increase? What useful work will the elevator motor do? The height of one floor is 5m .
• Above water surface
  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.
• Wheelchair
  The boy pushes the wheelchair with a force of F1 = 20N. The wheelchair exerts a force of F2 on the boy. How large is this force?
• Car
  At what horizontal distance reaches the car weight m = 753 kg speed v = 74 km/h when the car engine develops a tensile force F = 3061 N. (Neglect resistance of the environment.)
• Mushrooms
  Mushrooms lose 90% by weight drying. How many fresh mushrooms are needed for 5 kg of dried mushrooms?
• The car
  The car weight 1280 kg, increased its speed from 7.3 m/s to 63 km/h on a track of 37.2 m. What force did the car engine have to exert?
• Center of gravity
  The mass points are distributed in space as follows - specify by coordinates and weight. Find the center of gravity of the mass points system: A₁ [1; -20; 3] m₁ = 46 kg A₂ [-20; 2; 9] m₂ = 81 kg A₃ [9
• The bridge
  A vehicle weighing 5,800 kg passes 41 km/h on an arched bridge with a radius of curvature of 62 m. What force is pushing the car onto the bridge as it passes through the center? What is the maximum speed it can cross over the center of the bridge so that
• Hydrostatic force
  What is the hydrostatic force applied to an area of 30 cm² in the water at a depth of 20 m? (Water density is 1000 kg/m³)