The new block is made of a different material and has a coefficient of static friction μ = 0.7. Minimum mass?
Welllll, since we are on an incline we know that Fg = m*g*sin(theta) and Fn = m*g*cos(theta). So first we look at just block one, obvious since there is no friction on it, the block will slide down because of the force due to gravity. Since it is on an incline not all of that force pulls him down, some pushes him down into the ramp, so thats why we have Fg = m*g*sin(theta) So we know the force that m1(frictionless box) is getting pulled down is Fg1 = m1*g*sin(theta) Now since we want to stop it the second block with friction is attached. The equation to calculate friction is: Ff = Fn* u ...where u = mu or coefficient of friction as stated earlier we know Fn and can substitute in for that, so: Ff = m2*g*cos(theta)*u But block two is going to want to slide down the ramp as well and we have to take his force due to gravity into account. So he too has: Fg2 = m2*g*sin(theta) Now newton second law tells us the sum of the Forces = m*a and since this is a static situation F = 0 So if we denote down the ramp as positive, we know: Fg2 + Fg1 - Ff = 0 m2*g*sin(theta) + m1*g*sin(theta) - m2*g*cos(theta)*u = 0 m2*g*sin(theta)-m2*g*cos(theta)*u = -m1*g*sin(theta) g is in every term and factoring out an m2 m2(sin(theta)-cos(theta)*u) = -m1*sin(theta) m2 = -m1*sin(theta) / (sin(theta)-cos(theta)*u) m2 = -(9.1 kg)*sin(25) / (sin(25)-cos(25)*0.7) m2 = 18.1581 kg Double check its right, been a long time since I took physics
Can I make a homemade slip n slide out of a rubber pond liner?
Ok, first I would suggest vinyl sheeting, but regardless whether vinyl or the pond liner the method is the same. Start by laying down the material in the site of your choosing. Take about 6 inches of the sides and fold them under then stake them down, after it is staked, the cross section should be in an S shape (the stakes should be on the bottom of the "S", the top of the "S" covers the stakes to prevent snags on clothing and also creates a "wall" to keep the water from running off the edge). If you have multiple lengths of rubber/vinyl, place the bottom most length first and then overlap the lengths by 6 inches going upwards. Side note, try to place sprinklers or something to provide showers of water periodically throughout the run, this will ensure consistent lubrication of the rubber, getting a burn from this material is easy and is not fun.
When a truck driver has to use the runaway truck ramp, should they use the e-brake?
In big trucks, the emergency brakes come on automatically when the air pressure drops. Which will happen when the truck hits the pit (runaway ramps are gravel pits that stop the truck by burying it) and the air lines will get ripped out of some chambers.There's another E-brake on big trucks, which will prevent runaways if used properly.The engine brake is more powerful than the engine, and will hold you back all the way down the hill, as long as you respect the hill.You should start down the hill at a speed that the retarder will hold you back without relying on the brake pedal, and if you do this, your brakes will not fade coming down the hill.My wife is brand new at trucking (my boss paid for her to get her CDL and she's now my codriver), and already has the hang of modulating the retarder to come down at exactly the speed she feels safe: she doesn't like coming down at highway speed (even if it's safe and the retarder can hold it), she does not like feeling like she's hurtling down the hill. She's never going to fade her brakes.I go down at the fastest speed at which the retarder holds me without the brake pedal, so my brakes are as cool as the proverbial cucumber.
Boat Ramp Etiquette-Loading- Is the order of vehicles or order of boats the proper order to load?
Here in CA, the ramp etiquette is with the truck/trailer line and not the boats in the water. Dropping a person off to get the truck/trailer is better for all concerned. This person can be dropped near the dock or near shore. People that dock their boats and then unload people and gear are inconsiderate of everybody still on the water. These people add 15-30 minutes to the retrieval time just to their own boat, not to mention everybody else still on the water. When retrieving the boat from the water, everything should stay on the boat until the boat is on the trailer and well clear of the ramp as a courtesy for your fellow boaters. The object is to get the boat loaded and off the ramp as quickly as possible for the next person in the staging line with a truck/trailer. The boat lineup and staging is unimportant. Once a driver is dropped off, the boat should be pulled away from the dock to allow the next boat to drop a driver off to get their truck/trailer. NO ONE should have their boat parked at the dock without a truck/trailer backing into the water NOW. Learn to do a "Live Engine" retrieve! This is were the truck/trailer backs into the water and the boat is driven onto the trailer. The tips of the bunkers are just at the top of the water and the boat powers up the bunkers and the truck driver helps to guide the boat driver to the trailer. Once the hull touches the bunkers, it'll self right. Power the boat just enough to the "Bump Stop" and attach the Winch hook and pull tight, then attach the safety hook to the eye. Kill the engine and "Trailer UP" the outdrive if you have one. Truck driver now pulls forward and fully clear of the ramp area with everyone still onboard to an appropriate unloading area. There you'll do everything to remove gear, people and attach safety equipment for the road ahead. My wife and I do this with a 26' Express Cruiser everywhere, and get thumbs up from everyone on the ramp. We are usually on the ramp for under 5 minutes total! The ramp at days' end is always awful, don't make it worse by parking the boat at the ramp then getting the truck/trailer and everyone standing around doing nothing. Boaters still in the water are tired and want to get home too. So to give you an answer, you are in the wrong on this one.
Two blocks made of different materials connected together by a thin cord, slide down a plane ramp inclined at?
Two blocks made of different materials connected together by a thin cord, slide down a plane ramp inclined at an angle θ to the horizontal as shown in Fig. 5-28. The masses of the blocks are m1 and m2, and the coefficients of friction are µ1 and µ2. http://www.webassign.net/gianpse3/5-28.gif Figure 5-28 If m1 = m2 = 5.0 kg, µ1 = 0.25, µ2 = 0.33, and θ = 31°, determine the following. (a) the acceleration of the blocks ________m/s2 (down the ramp) (b) the tension in the cord ________N
Two bodies of different mass slide down an incline, which will reach the bottom first?
The observed fact, from Galileo through sensitive modern "fifth force" experiments, that gravitational acceleration is independent of mass is an important and deep keystone of reality and our framework for understanding it. It means the same "m" appears in F=ma and in F=GMm/r^2... and ultimately allows us to interpret general relativity and gravity as geometry rather than interaction forces.Good physics teachers are accordingly motivated to spend time in class and on assigned problems making sure the concept is well absorbed!Edit to keep a Quora bot happy:Of course, on a real world table top friction complicates things! There’s a reason why Scouting’s Pinewood Derby races have rules about weight.
How much would it cost to make a Homemade slip n slide?
how much would it cost for the plastic tarp? my mom seems to think its gonna be really expensive. Can you give me an estimated price, it doesnt have to be exact i just need a general idea of how much