Several objects were dropped from a balcony. Using the data below, determine which statements must be true regarding the rate of force of each falling object. Neglect (ignore) air resistance. Object Mass Diameter Height of drop Tennis Ball 0.06 kg 6.6 cm 5 m Baseball 0.15 kg 74 cm 5 m Bowling Ball 5 kg 21 cm 5 m Golf Ball 0.04 kg 4.3 cm 5 m Statement 1: All balls hit the ground at the same time Statement 2: All balls hit the ground with different forces Statement 3: The bowling ball hit the ground first and the tennis and golf ball hit the ground last Statement 4: It is not possible to tell how much force each ball hit the ground with

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.

What belongs in the areas marked x and y? x: the internal energy of a piston system increases as heat is added and rises to a cool area y: as thermal energy is added to a container, some of the energy is lost to the environment x: as thermal energy is added to a container, some of the energy is lost to the environment y: the internal energy of a piston system increases as heat is added and rises to a cool area x: a cold spoon placed in hot liquid gets warmer y: thermal energy is converted to light energy x: thermal energy is converted to light energy y: a cold spoon placed in hot liquid gets warmer

Tsunamis are fast-moving waves often generated by underwater earthquakes. in the deep ocean their amplitude is barely noticeable, but upon reaching shore they can rise to an astonishing height of a six-story building. one tsunami generated off the aleutian islands in alaska, had a wavelength of 897km and traveled a distance of 3280km in 4.18h. (a) what was the speed (in m/s) of the wave? find the waves (b) frequency and (c) period.