Scientific experiments are specially designed to test explanations for an observed phenomenon. A student decides to conduct an e
xperiment to determine the effect that the amount of time spent in the sunlight has on the overall growth of a plant. The student will conduct the experiment using two identical plants that will only spend different amounts of time in the sunlight. All other aspects needed for growth will remain identical for each. In the experiment described, what would the amount of water given to each plant be considered? a. an observation
b. a dependent variable
c. an independent variable
d. a control
The amount of water given is a control. D) because, if a plant grows bigger as a result of the water, and not the sun this would disrupt the experiment.
"Effort" usually refers to the applied force. An inclined plane decreases the force required while increasing the distance that the force is exerted over. So even though there's less force needed, the amount of work stays the same.
The momentum after collision is given by (m1+m2)v where m1 is the mass of car A, m2 us the mass of car B while v is the common velocity after collision. Therefore, momentum=(2000+4000)5=30000kgm/s to the right.