1. the oscillation frequency of the swing is 0.40hz. explain the physical meaning of this number 2. a flying insect in 60s wings sums up 3,000 together. what is the period of fluctuation of the insect wings

3. which variables describing the fluctuations (amplitude, period, frequency) do not change when the fluctuations are free, i. y. inhibitors

4. calculate 0.17m long mathematical pendulums with oscillation frequency

5.

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

If an electric circuit is not grounded it is best to reach out and touch it to provide the ground a.true or b.false

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.