Quarry Crane Mastering Physics?
I use the regualr bags all the timeAs long as they are sealed it doesn't make any difference I just opened a couple servings of Green Chile Stew that has been in the freezer since ChristmasIt is just fine and even more delicious than it was then!
Maybe if you only need top store for a day or so, but any time I have used ziplocs in the freezer for longer than that, they still got freezer burnt inside the baggie.
I use ziplocs all the time for freezing foodJust make sure you squeeze out any excess air around the food when you seal them, then you will not get freezer burn.
a) The tension T_3 is just the weight of the block, providing the block is at rest or moving up at a constant speedT_3 mg b) For this what I did was first to determine the angle between the two polesSince the poles are of equal length, rope 2 makes the same angle with both poles ie θSo the angle between the two poles is π-2θThis angle is the same as the angle between rope 1 and the tilted poleNow we can find the torque that rope 1 applies about point O To find the torque we need the force rope 1 applies to the end of the tilted pole, in the direction perpendicular to the length of the pole in the drawingThis makes an angle of π/2 - (π-2θ) 2θ - π/2 to rope 1 So the torque applied by rope 1 about point O is τ(1) Lmgcos(2θ-π/2) Lmgsin(2θ) Now we can find the torque applied about point O by rope 2 This torque τ(2) must equal τ(1) so that there is no movement in the tilted poleUsing the same method as for finding τ(1), noting that the angle between rope 2 and the tilted pole is θ and using T as the tension in rope 2 you should be able to show that τ(2) LTsin(θ) Now τ(2) τ(1) LTsin(θ) Lmgsin(2θ) Tsin(θ) mgsin(2θ) 2mgsin(θ)cos(θ) (using a trig identity) T 2mgcos(θ)
