Answer:
The focal lenth (F) =+10.0cm
Explanation:
The formular for combined focal length (F) is given as;

In this question,
F1 = 20cm
F2 = -30cm
Plugging the values into the formuar above,

![1/f = 0.05 - 0.033[tex]1/f = -0.017f = [tex]1/ -0.017](https://tex.z-dn.net/?f=1%2Ff%20%3D%200.05%20-%200.033%3C%2Fp%3E%3Cp%3E%5Btex%5D1%2Ff%20%3D%20-0.017%3C%2Fp%3E%3Cp%3Ef%20%3D%20%5Btex%5D1%2F%20-0.017)
f = 58.82cm
i.e. the combination behaves as a converging lens (because of the postive sign) of focal length 58.82cm .
Adjust the height of the wooden rod so that it just touches the surface of the water. Switch on the lamp and motor and adjust the speed of the motor until low frequency waves can be clearly observed... Count the number of waves passing a point in ten seconds then Divide by ten to record frequency.
Answer:
A- Martin brings his friends home to meet grandpa.
Explanation:
took the test.
Answer:
11:10 will be the time. reflection causes the object to be flipped when you see its image at the mirror
Answer:
density is defined as the amount of mass contained in unit volume of a body .its si unit is kg/m*3