You want to design a toy puppy that will bark whenever anyone walks past its sensor. which type of electromagnetic radiation would your design use?

a. ultraviolet radiation
b. visible light
c. gamma rays
d. microwaves

When a neutral charge, comes into contact with a positive charge they repel each other nothing happens the neutral charge becomes negative they attract each other

Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.

Aphysical change is a change in the size, shape,, or stafe of matter true or false