<h2>
Answer: 1000 J</h2>
The Work 
done by a Force 
refers to the release of potential energy from a body that is moved by the application of that force to overcome a resistance along a path.
It should be noted that it is a scalar magnitude, and its unit in the International System of Units is the Joule (like energy). Therefore, 1 Joule is the work done by a force of 1 Newton when moving an object, in the direction of the force, along 1 meter:
Now, when the applied force is constant and the direction of the force and the direction of the movement are parallel, the equation to calculate it is:
(1)
When they are not parallel, both directions form an angle, let's call it 
. In that case the expression to calculate the Work is:
(2)
For example, in order to push the 200 N box across the floor, you have to apply a force along the distance 
to overcome the resistance of the weight of the box (its 200 N).
In this case both <u>(the force and the distance in the path) are parallel</u>, so the work performed is the product of the force exerted to push the box 
by the distance traveled . as shown in equation (1).
Hence:
>>>>This is the work
Answer:
1) a = 6.14 km
2) b = 4.69 km
Explanation:
Let the first building be A, second building be B and third building be C.
Now, bearing of A = 4.76 km in a direction 37° north of east
Bearing of B = 69° west of north
Bearing of C = 28° east of south
Thus if this 3 points form a triangle, we will have the following angles;
Angle at point A = 28 + (90 - 37) = 81°
Angle at point B = 28 + (90 - 69) = 49°
Angle at point C = 180 - (81 + 49) = 50°
Now, the distance between second and third building is "a" which is represented by BC in the triangle attached while the given distance of 4.76 represents side AB. Thus;
Using sine rule, we can find "a".
a/sin 81 = 4.76/sin 50
a = 6.14 km
B) distance between first and third building is AB in the triangle depicted by "b".
Similar to the first problem, we will use sine rule again.
b/sin49 = 4.76/sin 50
b = 4.69 km
Most geologists accept radiometric dating techniques as valid because radioactive elements decay at a constant and measurable rate.
Answer: Option C
<u>Explanation:</u>
Scientists prefer radioactive dating to carbon dating because it is more accurate in measuring. The analysis depends upon the radioactive decay of radioactive isotopes of any matter in a given rock or soil.
The parent atoms and daughter atoms are compared while studying, and hence age can be calculated easily. Radioactive decay depends upon the given half-life of the atom, which is a constant and is known. So, it would be very easy to calculate the number of progeny atoms and parent atoms and find out their age.
Answer: 6.47m/s
Explanation:
The tangential speed can be defined in terms of linear speed. The linear speed is the distance traveled with respect to time taken. The tangential speed is basically, the linear speed across a circular path.
The time taken for 1 revolution is, 1/3.33 = 0.30s
velocity of the wheel = d/t
Since d is not given, we find d by using formula for the circumference of a circle. 2πr. Thus, V = 2πr/t
V = 2π * 0.309 / 0.3
V = 1.94/0.3
V = 6.47m/s
The tangential speed of the tack is 6.47m/s
