Answer:
Total distance (in metres)= 80+125+45=250
Total time (minutes) =10
250/10
=25
Explanation:
b. refraction.
c. diffraction.
d. polarization.
B) one fixed position pulley attached to a fixed point above the object that is being lifted
C) no pulleys just a string attached to an object that is being lifted
D) one moving pulley attached to the object that is being lifted
Answer;
D) one moving pulley attached to the object that is being lifted
Explanation;
-Pulleys are powerful simple machines. They can change the direction of a force, which can make it much easier for us to move something.
-A fixed pulley consists of a wheel fixed to a shaft and is used in conjunction with a belt to transfer energy to another fixed pulley. A movable pulley consists of a shell, a movable wheel and a rope. Movable pulleys are also know as block and tackle.
-One moving pulley attached to the object that is being lifted decreases the amount of effort force needed to lift an object.