Other Physics Answers

Directions: Draw the following vectors using your ruler and protractor. Write your answer on a separate sheet of paper. Use the scale (1 cm = 10 units )

1. a cart pushing 40 Newton 450 South of East

2. a car moving 15 m/s2 250 South of West

3. a train covered 120 km South

4. a motorcycle accelerating 20 m/s2 250 North of East 5. a barbel is lifting 20 N force upward

A 20g steel weight is placed on the edge of a 30cm diameter plastic disk. The coefficient of static friction between the steel weight and plastic disk is 0.4. At what angular velocity, ω will the weight slide off the disk? Your solution should include “known”, a pictorial representation, a physical representation and a free-body diagram. Hint: Apply Newton’s second law using v = rω, instead of v, as in the example.

Pictorial Representation

a. sketch showing important points in the motion

b. coordinate system

c. symbols for knowns and unknowns Known: Find:ωmax

2) Physical Representation

a. motion diagram

b. force identification

c. free-body diagram

3) Mathematical Representation

a. start with Newton’s first or second law

b. include other information as needed

c. solve!

2 nd law for r-axis 2 nd law for z axis

The radius of the outer sphere of a spherical capacitor is five times the radius of its inner shell. What are the dimensions of this capacitor of its capacitance is 5.00 pF?

an example of potential energy

Calculate the energy carried by an x-rays of wavelength 7.5×10^-10m(h=6.6×10^-34js, vorc=3×10⁸m/s)(Hmt:E=hc)

 A long jumper leaves the ground with an initial velocity of 12 m/s at an angle of 28-degrees above the horizontal. Determine the time of flight, the horizontal distance, and the peak height of the long-jumper.

 A soccer ball is kicked horizontally off a 22.0-meter high hill and lands a distance of 35.0 meters from the edge of the hill. Determine the initial horizontal velocity of the soccer ball. 

 A student’s travel from his home to school is described as follows: 22 m westward, 35 m southeast, and 17 m, 15° north of east. Compute for his displacement.

A hiker starts at his camp and moves the following distances while exploring his surroundings: 255 m east, 125 m at an angle 30.0° north of east, and 178 m at an angle 12.0° south of east. Find his resultant displacement from camp.