Answer:
A) 29.4 m 17.0 m; B) 2 m
Explanation:
If a vector is 34.0 m in length and is directed 60.0° east of north (which means 30.0° over the horizontal), then its coordinates will be:
Horizontal: (34.0 m)cos(30.0°)=29.4 m
Vertical: (34.0 m)sin(30.0°)=17 m
If one person walks 8.0 meters in a straight line and then walks 5.0 meters in another straight line, then the minimum displacement would be to go back over his tracks, displacing himself 8m-5m=3m, while the maximum displacement would be going straight ahead, displacing himself 8m+5m=13m. Any answer outside this interval is impossible (2m).
Let l = Q/L = linear charge density. The semi-circle has a length L which is half the circumference of the circle. So w can relate the radius of the circle to L by
<span>C = 2L = 2*pi*R ---> R = L/pi </span>
<span>Now define the center of the semi-circle as the origin of coordinates and define a as the angle between R and the x-axis. </span>
<span>we can define a small charge dq as </span>
<span>dq = l*ds = l*R*da </span>
<span>So the electric field can be written as: </span>
<span>dE =kdq*(cos(a)/R^2 I_hat + sin(a)/R^2 j_hat) </span>
<span>dE = k*I*R*da*(cos(a)/R^2 I_hat + sin(a)/R^2 j_hat) </span>
<span>E = k*I*(sin(a)/R I_hat - cos(a)/R^2 j_hat) </span>
<span>E = pi*k*Q/L(sin(a)/L I_hat - cos(a)/L j_hat)</span>
Answer:
Neglecting air resistance, the only force acting on a projectile is gravity.
This force causes the object to accelerate.
Explanation:
As a projectile moves upward, there is a downward force and a downward acceleration due to force of gravity. That is, as the object is moving upward, force of gravity acting on the projectile is causing a steady slowing down of the projectile.
Hence, Gravity is the downward force upon a projectile that influences its vertical motion and causes the parabolic trajectory that is characteristic of projectiles.
From Newton's law of motion, it suggest that force is required to cause an acceleration and not motion. Therefore, force of gravity causes the object to accelerate downwards.
