Physics Units Level: High School
Does a negative acceleration necessarily imply that a body is slowing down ? What (or who ) determines the sign if the acceleration in a particular problem ?Physics Units Level: High School
By definition , 1 inch precisely equals 2.5400 centimeters . A length is measured to be 3.2 feet , and after conversion to centimeters this length is reported to be 97.54 centimeters . Explain what is wrong with this conclusion .Physics Kinematics Level: High School
A punter kicks a punt 4.0 seconds later the punt return fields the punt 40 yards down field . Assume that he receives the ball at the same height that it was punted .Find ,a. Vxo
b. Vyo
c. Vo
Physics Kinematics Level: High School
A ball is thrown from the ground vertically upward at 20 m/s .(a) how high does it go up ?
(b) how long to reach its highest point
(c) how long till it hits the ground ?
(d) What is the velocity that it has when it returns to the level from which it started ?
Physics Kinematics Level: High School
A mountain climber throws a stone straight down into a mountain pool 50 meters below . The stone has an initial velocity of 2 m/s straight down .(a)How long till the stone hits the water .
(b) Suppose he throws a second stone 1 second later . With what velocity would he have to throw the second stone if both stones hit at the same time .
Physics Kinematics Level: High School
A plane flies 40 km due north in level flight . The pilot then flies 100 km at a heading of 45 degrees east of north . Next he flies 20 km due south . Find the displacement vector that describes his final position .Physics Kinematics Level: High School
A projectile is launched into the air with a velocity of 30 m/s at an angle of 30 from the horizontal . Assume that there is no friction and that the ground is level . Find Vxo and Vyo , the maximum height the projectile reaches , the distance it travels when it hits the ground , and the final velocity of the ball (magnitude and direction)Physics Measurements Level: High School
Given a sheet of paper and a ruler , can you think of two indirect measurements you could make ? What direct measurements would you need in each case ?(i) Perimeter 2 [l+b]
(ii) Area l x b
Direct measurements .(i) length l
(ii) width b
Physics Units Level: High School
Significant figures
Alice measures the diameter of a CD and gets a value of 117 mm , so she reports the value of the circumference as 367.5663404700058 mm . What wrong with this picture ?Physics Work,Power & Energy Level: High School
The diagram shown at depicts two pucks on a frictionless table. Puck II four times as massive as puck I. starting from rest, the pucks are pushed across the table by two equal forces.
(a) Which puck will have the greater kinetic energy upon reaching the finish line ? Explain
(b) Which puck will reach the finish line first ? Explain.
Physics Kinematics Level: High School
A sky diver , with parachute unopened, falls 625 m in 15 seconds . Then she opens her parachute and falls another 356 m in 142 s . what is her average velocity(both magnitude and direction) or her entire fall ?Physics Kinematics Level: High School
An 18 year old runner can complete a 10. km course with an average speed of 4.38 m/s . A 50 year old runner can cover the same distance with an average speed of 4.27 m/s . How much later should the younger runner start in order to finish the course at the same time as the older runner ?Physics Kinematics Level: High School
Give an example for which the velocity of an object is zero for just an instant of time , but its acceleration is zero .Physics Vectors Level: High School
Two buses depart from Chicago , one going to Newt York and one to San Francisco . Each bus travels at the speed of 30 m/s . Do they have equal velocities ? Explain .Physics Vectors Level: High School
The magnitude of the force vector F is 280 newtons . The x component of this vector is directed along the +x axis and has a magnitude of 150 newtons . The y component points along the +y axis(a) Find the direction of F relative to the +x axis
(b) Find the component of F along the +y axis