How to tell if two objects are in thermal equilibrium

1. the objects have the same temperature

2. the objects are the same size

3. the objects are touching each other

4. the objects temperatures are changing

Look at the densities of the jovian planets given in figure 1. which of the following statements best describes the pattern of jovian planet densities?

Sully uses a battery and a coil of wire to create an electromagnet. Using the same materials, if he wants to increase the strength of his electromagnet, he must the number of loops in the coil of wire along its length.

The current in a long solenoid of radius 6 cm and 17 turns/cm is varied with time at a rate of 5 A/s. A circular loop of wire of radius 8 cm and resistance 4 Ω surrounds the solenoid. Find the electrical current induced in the loop (in µA).

An upward moving object must be experiencing (or at least usually does experience) an upward force.

Define Momentum? ...

4. How far does a car travel in 90 seconds if it is traveling at a speed of 55 m/s?

Total energy input is 1400 and my efficiency is 80% so what is the useful energy output in jules?

What is the force of gravity acting on a 2000-kg spacecraft when it orbits two Earth radii from the Earth's center (that is a distance r=6380 km above the Earth's Surface. The mass of the Earth is 5.98 x 1024 kg.

An LC circuit has a 6.00 mH inductor. The current has its maximum value of 0.570 A at t = 0s. A short time later the capacitor reaches its maximum potential difference of 66.0 V. What is the value of the capacitance?

The first law of thermodynamics states that ΔE = Q - W. Is this also a statement of the principle of conservation of energy? Yes, the heat added and the change in internal energy of the gas equal the work done by the piston.