Static electricity usually develops when objects are rubbed against each other. the rubbing process causes some electrons from one of the objects to relocate to the other object. the object that loses electrons then has more protons than electrons and thus develops an overall positive charge. the object that gains electrons then has more electrons than protons and thus develops an overall negative charge. here a balloon is rubbed against a person’s hair. electrons move from the hair to the balloon. the surface of the balloon now has more electrons than protons, so it develops a negative charge. the surface of the hair now has more protons than electrons, so it develops a positive charge. flyaway hair is caused by the fact that each individual strand of hair now has a positive charge. because like charges repel, each piece of hair repels every other piece of hair, making them stand out as far away from each other as possible. what would be good summary of the lab from the information above?

a.) static electricity is based off of gravity

b.) static electricity is the movement of electrons. electrons will move from the hair to the balloon.

c.) static electricity can be created in water.

d.) balloons are full of air.

A6,600 kg train car moving at +2.0 m/s bumps into and locks together with one of mass 5,400kg moving at -3.0m/s. what is their final velocity? +0.50 m/s -1.0 m/s +2.5 m/s -0.25 m/s

Follow these directions and answer the questions. 1. shine a pencil-thin beam of light on a mirror perpendicular to its surface. (if you don't have a laser light as suggested in the video, you can make a narrow beam from a flashlight by making a cone from black construction paper and taping it over the face of the flashlight.) how does the light reflect? how does the relationship of incident to reflected ray relate to the reflection of water waves moving perpendicular to a barrier? 2. shine a pencil-thin beam of light on a mirror standing on a sheet of paper on the table (or floor) so that you can mark the incident ray and reflected ray. (you can support the mirror from the back by taping it to a wooden block.) 3. mark a line on the paper representing the reflective surface. (the reflective surface of a mirror is usually the back edge.) 4. draw a dashed line perpendicular to the mirror surface at a point where the incident and reflected ray meet. this perpendicular is called a normal to the surface. 5. measure the angles between the rays and the normal. the angle of incidence is the angle formed by the incident ray and the normal to the surface. the angle formed by the reflected ray and normal is called the angle of reflection (r). what is the angle of incidence? what is the angle of reflection? 6. repeat for several different angles. (see report sheet for details.) what appears to be the relationship between the angle of incidence and angle of reflection? in science 1204, what was the relationship for these two angles made by the reflection of waves in a ripple tank? 7. roll a ball bearing so that it hits a fixed, hard surface (a metal plate) at several angles (including head-on). observe the way in which the ball bearing reflects. what generalization can you make about how a ball bearing reflects from a wall? have you proved that light can only behave like a wave?

What are the starting materials for nuclear fission? two small nuclei two large nuclei a neutron and a large nucleus a neutron and a small nucleus