Is space-time and concept of "now" an illusion?

Why must you use temperature to specify how hot or cold something is?

All of the following are examples of convection currents, except: A. Warm air rising B. Cold water sinking to the bottom of the lake C. Water flowing through pipes D. Steam from hot soup rising into the air

If a 2000 kg truck accelerates at a rate of 2m/s2, what is the force generated by the truck?

Which of the following is true about density and states of matter for most substances? A substance is denser as a solid than as a gas. B substance is denser as a liquid than as a solid. C substance is denser as a gas than as a liquid.

A periodic transverse wave that has a frequency of 10 Hz travels along a string. The distance between a crest and either adjacent trough is 2.5 m. What is the wavelength?

You create a transformer by wrapping wire around an iron nail. The number of turns are: Primary (500); Secondary (2500). The Primary voltage is 3.00 V. The Secondary current is 200 mA.

A 90kg cannon fires 100kg shell with muzzle velocity of 75m/s. Calculate the recoil velocity of the cannon relative to the ground

The planet XYZ traveling about the star ABC in a circular orbit takes 24 hours to make an orbit. Assume that the orbit is a circle with radius 89 comma 000 comma 00089,000,000 mi. Find the linear speed of XYZ in miles per hour.

Your heart pumps 80 g of blood with each beat. The blood starts from rest and reaches a speed of 0.60 m/s in the aorta. If each beat takes 0.16 s, the average force exerted on the blood is a. 3.0" 102 N b. 0.22 N c. 0.16 N d. 0.30 N e. 0.98 N

What is the formula for calculating the mass when i have the number of volume and density