Answer:
B.) its velocity is zero and its acceleration is negative (downward).
Explanation:
When the ball is thrown upwards in the air, the ball starts with its velocity being high and positive upwards against the force of gravity. Due to force of gravity pulling the object to the center of the earth, its velocity decreases as it reaches the maximum height where the velocity is instantaneously zero. At this maximum height its acceleration is -9.81 m/s².
Potential energy because it has enough energy to do work but non has been done yet.
Answer:
Explanation:
A concave mirror is a curved mirror that is coated outwards. The outer part of the mirror is always coated. The nature of image formed by an object placed in front of a concave mirror can be real or virtual depending on the distance of the object on the axis from the mirror. The only time the object produces a virtual image is when it is placed between the focus and the pole of the mirror. The virtual image formed is a "MAGNIFIED and upright image"
For a convex mirror, the inner part is always coated and the nature of the image formed by the object doesn't depend on the distance between the image and the mirror. No matter where the object is placed, the image formed will always be virtual, upright and DIMINISHED. This means that magnification is always less than 1.
For a plane mirror, the nature of the image produced by a plane mirror also virtual because it is always formed behind the mirror. The size of the image formed is always THE SAME as that of the object. This means that the magnification is always equal to 1.
a) In summary, the difference between virtual images produced by concave, plane, and convex mirrors is that virtual images produced by concave mirror are MAGNIFIED, virtual images produced by plane mirror are THE SAME SIZE as that of the object and virtual images produced by convex mirrors are always DIMINISHED.
b) Magnification is defined as the ratio of the image distance to the object distance. Mag = v/u
Note that object distances are always positive, hence it is only the image distance that can either be positive or negative which in turn affects the magnification causing it to be positive or negative.
Negative image distance shows that the image is virtual while positive image distance shows that the image is real.
A negative magnification therefore shows that the nature of the image is a virtual image.
Answer:
degree
Explanation:
given data:
accoding to the snell's law
where n1 is refracting index of air = 1
n2 is refracting index of glass = 1.55
putting all value to get angle mad by incident ray with normal
degree
Life cycles occur in a variety of forms, all involving the exploitation of one or more hosts. Those that must infect more than one host species to complete their life cycles are said to have complex or indirect life cycles, while those that infect a single species have direct life cycles.
If a parasite has to infect a given host in order to complete its life cycle, then it is said to be an obligate parasite of that host; sometimes, infection is facultative — the parasite can survive and complete its life cycle without infecting that particular host species. Parasites sometimes infect hosts in which they cannot complete their life cycles; these are accidental hosts.
A host in which parasites reproduce sexually is known as the definitive, final or primary host. In intermediate hosts, parasites either do not reproduce or do so asexually, but the parasite always develops to a new stage in this type of host
