Answer:
<h2><em>
6000 counts per second</em></h2>
Explanation:
If a sample emits 2000 counts per second when the detector is 1 meter from the sample, then;
2000 counts per second = 1 meter ... 1
In order to know the number of counts per second that would be observed when the detector is 3 meters from the sample, we will have;
x count per second = 3 meter ... 2
Solving the two expressions simultaneously for x we will have;
2000 counts per second = 1 meter
x counts per second = 3 meter
Cross multiply to get x
2000 * 3 = 1* x
6000 = x
<em></em>
<em>This shows that 6000 counts per second would be observed when the detector is 3 meters from the sample</em>









☯ <u>Using 1st equation of motion </u>











☯ <u>Now, Finding the force exerted </u>







☯ <u>Hence</u>, 

Answer:
The image height is 3.0 cm
Explanation:
Given;
object distance,
= 15.0 cm
image distance,
= 5.0 cm
height of the object,
= 9.0 cm
height of the image,
= ?
Apply lens equation;

Therefore, the image height is 3.0 cm. The negative values for image height indicate that the image is an inverted image.
Answer:
Sam will do 1152 J of work to stop the boat
Explanation:
Work: This is defined as the product of force and distance, the S.I unit of work is Joules. At any point in science, during calculation Energy and worked can be interchange because they have the same unit.
E = W = 1/2mv²................ Equation 1
Where E = energy, W = work, m = mass, v = velocity.
Given: m = 900 kg, v = 1.6 m/s
Substituting these values into equation 1
W = 1/2(900)(1.6)²
W = 450×2.56
W = 1152 J.
Therefore Sam will do 1152 J of work to stop the boat
The sun is the primary source of light. Other artificial sources are light bulb, torch light and some others. Thats all i can think of.