A light spring with a force constant of 22 N/m is connected to a wall and to a 1.8-kg toy bulldozer. When the electric motor in the bulldozer is turned on, it stretches the spring for a distance of 35 cm before its tread begins to slip on the floor and it accelerates back towards the wall at a rate of 0.784 m/s2. What is the coefficient of dynamic friction between the treads and the floor?

Gunpowder residue is most likely to show up where on a shooters hands

Acarpenter builds an exterior house wall with a layer of wood 2.9 cm thick on the outside and a layer of styrofoam insulation 2.3 cm thick on the inside wall surface. the wood has k=0.080w/(m⋅k), and the styrofoam has k= 0.010 w/(m⋅k). the interior surface temperature is 19.0 ∘c , and the exterior surface temperature is -15.0 ∘c . a.)what is the temperature at the plane where the wood meets the styrofoam? celsius b.)what is the rate of heat flow per square meter through this wall? /m^2

Takumi works in his yard for 45 minutes each saturday. he works in the morning, and he wears sunscreen and a hat each time he works in the yard. what does takumi hope to reduce through his actions? the likelihood of stochastic effects, such as dna mutations the severity of stochastic effects, such as cancer the severity of non-stochastic effects, such as cancer the likelihood of non-stochastic effects, such as radiation sickness