The peak force on a runner’s foot during a race is found to be vertical and three times his weight. What is the peak force on the foot of a runner whose mass is 85.0 kg? If the peak force is upward, enter a positive value. If the peak force is downward, enter a negative value.

An ideal polarizer with its transmission axis rotated 30 degrees to the vertical is placed in a beam of unpolarized light of intensity 10w/m^2. after passing through the polarizer, what is the intensity of the beam? a. 8.7 w/m^2 b. 7.5 w/m^2 c. 5.0 w/m^2 d. 10 w/m^2 e. 2.5 w/m^2