Aday has 86,400 second (s). notice that the decimal point is to the far right of the number. the first part of scientific notation is a number between 1 and 10. move the decimal point to the left to obtain 8.64, which equals m in our traditional notation. the value for n is given by the number of places the decimal point was moved from its location in 86,400 to 8.64. thus, 86,400 s = 8.64×104 s. because the decimal was moved four places to the left (and the value is larger than 1), the exponent is a positive integer. if you had a very precise clock, you could write this as 8.640×104 s, or 8.6400×104 s. the number of digits you keep in the first part of the notation describes the precision of your value and determines the number of significant digits.

Astudent throws a water balloon with speed v0 from a height h = 1.76 m at an angle θ = 21° above the horizontal toward a target on the ground. the target is located a horizontal distance d = 9.5 m from the student’s feet. assume that the balloon moves without air resistance. use a cartesian coordinate system with the origin at the balloon's initial position. (a) what is the position vector, rtarge t, that originates from the balloon's original position and terminates at the target? put this in terms of h and d, and represent it as a vector using i and j. (b) in terms of the variables in the problem, determine the time, t, after the launch it takes the balloon to reach the target. your answer should not include h. (c) create an expression for the balloon's vertical position as a function of time, y(t), in terms of t, vo, g, and θ. (d) determine the magnitude of the balloon's initial velocity, v0, in meters per second, by eliminating t from the previous two expressions.