Unit Conversion Worksheet

Transcription

1 Name: Period Date: Unit Conversion Worksheet Conversions 1 hour = 3600 seconds 1 mile = 5280 feet 1 yard = 3 feet 1 meter = 3.28 feet 1 km = 0.62 miles 1 light second = 300,000,000 meters 1 kg = 2.2 lbs 1 lb = 0.45 kg 1 quart = liters 1 m/s = 2.2 miles/hour 1 foot = 12 inches 1 inch = 2.54 cm = 25.4 mm Convert the following quantities. 565,900 seconds into days 17 years into minutes 43 miles into feet 165 pounds into kilograms 100 yards into meters 22,647 inches into miles 2678 cm into feet

2 60 miles per hour into meters per second 130 meters per second into miles per hour 1100 feet per second into miles per hour 53 yards per hour into inches per week 721 lbs per week into kg per second 88 inches per second into miles per day gallons per month into liters per hour 27 miles per gallon into kilometers per liter 186,282 miles per second into meters per second

3 Kinematics Review 1) A sprinter is running at 2.5 m/s. After a while, the sprinter begins to slow down at a constant rate of 2.00 m/s 2. How fast is the sprinter after he has been slowing down for 0.4 m? 2) A school bus is going down the street at 30 m/s and begins to slow down at a constant rate to stop in exactly 12 seconds. What is the displacement of the school bus in this time interval?

4 3) A ball is rolling down a hill. It s initial velocity at the top of the hill was 7.0 m/s and it experiences a constant acceleration of 2.0 m/s 2. What is the final velocity after 4.0 seconds? 4) I throw my water bottle straight up in the air with initial velocity of 16 m/s. a) What is the water bottles displacement after 1.5 seconds? b) What is the max height reached by the water bottle?

5 Vector/Projectile Exam Review 1) You and your friends get in the car to go the store. To get there, you have to travel 15 miles east, 25 miles south, and then another 10 miles east. What is the resultant displacement? 2) At the store, you buy a slingshot. When you get somewhere safe, you fire a small pebble completely horizontally from the slingshot. If you were holding the slingshot at about 1.5 meters and the pebble lands 20 meters away, then what was the velocity of the pebble as it left the slingshot? 3) Your friend on the other hand, bought a bouncy ball. To test it out he throws it 2 meters at an angle 30 below the horizontal. At this point, it bounces off the floor, reflecting at angle 45 above the horizontal and traveling 3 meters before your other friend catches it. What is the resultant displacement? 4) Imagine an archer on the edge of a large cliff. If he shots an arrow horizontally and hears the arrow hit the floor below 4.5 seconds later (assuming sounds travels instantly here), then what is the height of the cliff in meters? 5) If the arrow landed 200m away, what velocity was it fired with? 6) Add these vectors: 15m/s, 38 W of S and 10m/s, 25 S of E 8m 40 E of N and 9m 30 E of S and 3m W 7) If a projectile fired horizontally has a final vertical velocity of -20m/s, how long was it in the air? 8) If the projectile from the previous problem landed 1500m away, what was its horizontal velocity? 9) A boat going 10m/s due east on a river that has a current pushing at 3m/s 30 S of E. What is the boat s resultant velocity? 10) A plane is flying due north at 20 m/s and it flying straight into a headwind of 10m/s. What is the plane s resultant velocity? How long would it take the plane to fly thirty thousand meters in these conditions (in hours)? 11) A ball rolls off a table 2 meters high. a) How long is it in the air? b) What is the vertical velocity of the ball when it strikes the ground? c) If the ball was rolled at 5m/s, then how far from the table did land?

6 Mr. Mack Physics Honors Name: Mrs. Poenariu 1) What acceleration will you give to a 24.3 kg box if you push horizontally with a net force of 85.5N? 2) A dog pulls a pillow with a force of 5 n at an angle of 370 above the horizontal. Find the x and y components of this force. 3) Draw the free body diagrams on a laundry basket in each of the following situations: a) at rest on a horizontal surface b) at rest on a ramp inclined at 25o above the horizontal c) in motion if is pulled with a force F under a 45o 4) Determine the magnitude of the net force of the object shown below, assuming the object is in space and these are the only forces acting on it. 5) A 600 kg elevator is accelerating upwards at 1.1 m/s 2. What is tension in the cable pulling it up? 6) A children s wagon is pulled from the handle with a force of 80N at angle 33 above the horizontal. If the coefficient of friction between the plastic wheels and the sidewalk is 0.11, then what is the magnitude acceleration of the wagon? 7) A taxi driver in San Francisco has to drive up a 38 hill. If the mass of his taxi is 1600 kg, then what force up the hill must the taxi exert in order to accelerate 0.5 m/s 2? 8) A piano is attached to a piano crane to be brought up to the third floor. If the cable attached to the piano is pulling upwards at 4200 N and the piano accelerates at 0.2 m/s 2, then what is the mass of the piano? 9) (Includes Kinematics) A bullet traveling at 500 m/s strikes a ballistics gel and comes to a complete stop within 35 cm. What was the net force actin on the bullet inside the ballistics gel? 10) The taxi driver in San Francisco broke down going up another hill. A tow truck attaches a cable to the taxi and accelerates it up the hill at 1.1 m/s 2. If the angle of incline is 22 and the coefficient of friction between the taxi s wheels and the road is 0.24, then what is the tension in the cable attached to the taxi? (Remember the mass of the taxi is 1600 kg). 11) A woman at an airport is towing her 20.0 kg suitcase at constant speed by pulling on a strap at an angle θ above the horizontal. She pulls on the strap with a 35.0 N force, and the friction force on the suitcase is 20.0 N. Draw the free body diagram of the suitcase. A) What angle does the strap make with the horizontal? B) What normal force does the ground exerts on the suitcase? 12) A 4.00 kg block pushed along the ceiling with a constant applied force of 85.0 N that acts at an angle of 55o with the horizontal. The block accelerates to the right at 6.00m/s2. Determine the coefficient of kinetic friction between the block and the ceiling.

7 Mr. Mack Physics Honors Name: Mrs. Poenariu 13) A 5.0 kg bucket of water is raised from a well by a rope. If the upward acceleration of the bucket is 3.0 m/s2. Find the force exerted by the rope on the bucket of water. 14) In 1988, a very large telephone constructed by a Dutch telecommunication company was demonstrated in the Netherlands. Suppose this telephone is towed a short distance by a horizontal force equal to 8670N, so that the telephone net acceleration is 1.3 m/s 2. Given that the coefficient of kinetic friction between the phone and the ground is 0.120, calculate the mass of the phone. 15) A child holds a sled at rest with a rope on a frictionless, snow-covered hill. The hill is inclined at 30. If the sled weights 77.0 N, find the (a) force exerted by the rope on the sled and the (b) magnitude of the normal force exerted by the hill on the sled. 16) Two forces are applied to a car in an effort to accelerate it. First force is 380N under an angle of 30.0 E of N, and the second force is 450N under an angle of 10.0 W of N. a) what is the resultant of these two forces? b) If the car has a mass of a 3200kg, what acceleration does it have?

8 Mr. Mack Physics Honors Name: P: Energy Exam Review 1) The largest turtle ever caught was in the US. Suppose the turtle was raised 5.45 m onto the deck of a research ship. It takes 4.60 x 10 4 J of work to lift the turtle this distance at a constant velocity. a) Draw and label a force diagram b) Find the weight of the turtle 2) The largest mincemeat pie ever created had a mass of 1.02 x 10 3 kg. Suppose that a pie with this mass slides down a frictionless ramp that is 18.0 meters long and inclined at 10. a) Draw and label a force diagram b) Find the work done by gravity c) Find work done by normal force 3) Susie Maroney from Australia set a women s record in long-distance swimming by swimming km in 24.0 hours. a) What was Maroney s average speed during this swim? b) If her mass is 55 kg, what was her kinetic energy when she was traveling her average speed?

9 Mr. Mack Physics Honors Name: P: 4) In 1990, Roger Hickey of California reached a speed of 35.0 m/s on his skateboard. Suppose it took 21 kj of work for Roger to teach this speed from a speed of 25.0 m/s. Using the Work-Kinetic Energy Theorem, Calculate Hickey s mass. 5) In 1992, Ukranian Sergei Bubka used a short pole to jump to a height of 6.13 meters. If the maximum potential energy associated with Bubka was 4.80 kj at the maximum height, then what was his mass. (Assume Bubka is at rest for an instant when he reaches max height) 6) April Moon holds the record for flight shooting in Archery. She fired an arrow that traveled 950 meters (almost 10 football fields, close to half a mile). It left the bow at a speed of 80 m/s. Suppose the arrow had a mass of 65 grams. a) What was the kinetic energy of the arrow when it left the bow? b) If the bowstring was pulled back 55 cm from its relaxed position, what was the spring constant of the bowstring? (Assume all energy was transferred and none was lost) 7) One species of eucalyptus tree, Eucalyptus regnens, grows to heights similar to those attained by California Redwoods. Suppose a bird sitting on the top of one of these drops an acorn. The speed of the acorn at the moment it is 50 meters above the ground is 42.7 m/s. a) Is the mass of the acorn required to solve this problem? b) How tall is that tree?

10 Mr. Mack Physics Honors Name: P: 8) In 1936, Col. Harry Froboess of Switzerland jumped into the ocean from the airship Graf Hindenburg, which was 120 meters above the water s surface. Assume Froboess had a mass of 72.0 kg. a) What was his kinetic energy at the moment he was 30 meters from the water s surface? b) What was his speed at that moment? 9) The first practical car to use a gasoline engine was built in London in The power generated by the engine was just 2984 W. How long would this engine have to run to produce 3600 J of work? 10) A 0.60 kg rubber ball has a speed of 2.0 m/s at point A and kinetic energy of 7.5 J at point B. Determine the following: a) the ball s KE at point A b) the ball s speed at point B c) the net work done on the ball from point A to point B 11) A 50 kg pole vaulter running at 10 m/s vaults over the bar. The vaulter s velocity when he is directly over the bar at the peak of his jump is 1.0 m/s. a) What was his total mechanical energy before the jump? b) How high was the jump? (In other words, how high when he is directly over the bar)

11 Mr. Mack Physics Honors Name: P: 12) For each of the following, indicate whether the work done on the object is positive or negative. i) The road exerts a friction force on a speeding car. ii) A rope exerts a force on a bucket as the bucket is raised up a well. iii) Air exerts a force on a parachute as the parachutist falls to Earth. 13) A spring of a jack-in-the-box is compressed a distance of 9.0 cm from its relaxed length and then released. The mass of the toy head is 50 grams and the spring constant is 80 N/m. a) Before it is released what is elastic potential energy stored in the spring? b) After it is released, what is the speed of the toy head the moment it passes through its equilibrium point (in other words, the moment the spring returns to its relaxed length)? 14) Is conservation of mechanical energy likely to hold in these situations? (Yes or No) i) A hockey puck sliding on frictionless ice ii) A toy car rolling on a carpeted floor iii) A baseball being thrown in the air iv) An object being dropped from an arbitrary height 15) A 50.0 kg student climbs up a 5 meter rope at constant speed. The student s power output during this time is 200 W. a) Draw a force diagram. b) Calculate the work done by the student? c) How long does it take the student to climb the rope?