Which is an example of the electromagnetic force? a. A compass needle points north toward Earth’s magnetic pole.
b. An iron nail rolls off a table and falls to the ground.
c. The moon pulls on the water in Earth’s oceans, causing tides.
d. Protons that make up a nitrogen atom stay together in the nucleus.

The position of a dragonfly that is flying parallel to the ground is given as a function of time by r⃗ =[2.90m+(0.0900m/s2)t2]i^− (0.0150m/s3)t3j^. a: at what value of t does the velocity vector of the insect make an angle of 34.0 degree clockwise from the x-axis? b: at the time calculated in part (a), what is the magnitude of the acceleration vector of the insect? c : at the time calculated in part (a), what is the direction of the acceleration vector of the insect?

Aspecimen of oil having an initial volume of 580cm^3 is subjected to a pressure increase of 4.0 mpa, and the volume is found to decrease by 0.40 cm^3. (a) what is the bulk modulus of the material? (b) what is the compressibility of the material?

A2000 kg car is rounding a curve of radius 200 m on a level road. the maximum frictional force the road can exert on the tires of the car is 4000 n. what is the highest speed at which the car can round the curve?