: Các dòng điện I1 = 4 A, I2 = 6 A chạy cùng chiều trong hai dây dẫn thẳng, rất dài, song song và cách nhau 10 cm. Vectơ từ trường do hai dòng điện
này gây ra tại một điểm nằm trên mặt phẳng chứa các dòng điện và cách đều
chúng sẽ:
A. hướng thẳng đứng lên trên và có độ lớn 8.10-6 T
B. hướng thẳng đứng xuống dưới và có độ lớn 9.10-6 T.
C. bằng 0.
D. hướng thẳng đứng lên trên và có độ lớn 10.10-6 T

Aball is thrown upward in the air, and its height above the ground after t seconds is h ( t ) = 57 t − 16 t 2 feet. find the time t when the ball will be traveling upward at 14.25 feet per second.

Next a skier is pulled by a tow rope up a frictionless ski slope that makes an angle of 15 with the horizontal. the rope moves parallel to the slope with a constant speed of 0.69 m/s. the force of the rope does 800 3 of work on the skier as the skier moves a distance of 8.4 m up the incline. (a) if the rope moved with a constant speed of 2.2 m/s how much work would the force of the rope do on the skier as the skler moved a distance of 8.4 m up the incline? at what rate is the force of the rope doing work on the skier when the rope moves with a speed of (b) 0.69 m/s and (c) 2.2 m/s?

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.