Answer:
An electroscope is a device which used to detect charge on an object. It consists of conducting sphere at top with a metal rod and metal leaves. This is enclosed in a glass jar. A charged object is brought near the top of the electroscope. this causes electrons to transfer to or from the charged object.
If the electroscope has charge, the leaves repel each other and move away from each other. This is because charge conducts from the metallic sphere through rod to both leaves. Having same charge, the leaves repel each other and open up. No change occurs in neutral state.
We cannot tell from an electroscope alone what kind of charge it has because the leaves have like charges and hence repel each other whether it is positive or negative charge. Thus, we cannot differentiate the charge.
Answer:c
Explanation:work is force x distance. The wall doesn’t move any distance in A so that’s not work. B involves tasks that do work but I don’t think this is what they’re going for. For a short instance while kicking a ball, your foot is applying a force to the ball which moves a distance before following its own trajectory after contact with your foot. Because the contact has a short duration and isn’t instantaneous, this is work
Answer:
<em>D. remains constant throughout the fall.</em>
Explanation:
<u>Horizontal Launching
</u>
We can launch an object in free air in three forms: vertically, horizontally or inclined. In any case, the only acting force to modify the object's velocity and make it go back to the ground is the force of gravity and it's always directed downwards. Unless friction or air resistance is considered, the horizontal motion is not affected because no force is acting in that direction.
The rock described in the question was launched at 3 m/s pointed horizontally. Immediately after launching, the rock starts to fall to the ground and gain vertical velocity, but the horizontal component remains the same until it completes the flight.
The D option is correct: the horizontal velocity of the rock remains constant throughout the fall
Answer:
D. A record of all the physical activity you complete in one week.
Explanation:
A "Fitness Log" allows you to keep track of your workout or exercise. Therefore, it is <em><u>a record of the different workout you've managed to complete within a time frame</u></em>. It gives you several information such as the<em> type of workout you've completed, its duration and the time of the day it was performed</em>. This makes a person motivated to exercise because he can see his progress. He may also include <em>his mood before and after workout</em> in order to become more mindful in exercising and many other things.