Question

1. The pendulum has the largest kinetic energy at the lowest point of its swing. TRUE or FALSE

2.      At what launch angle does a projectile go the farthest before it hits the ground

		90
		0
		30
		45
		60
		30 and 60

3. When you are loading your furniture into a moving truck, you will do less work if you use a shorter (and steeper) ramp, TRUE or FALSE

Answer 1

1. TRUE

Highest point of swing No kinetic energy Maximum gravitational potential energy Maximum kinetic energy Minimum gravitational potential energy

2. 45 degrees

3.FALSE

Answer 2

1.) false

2) 45

3.) false

Answer 3

1. TRUE

Highest point of swing No kinetic energy Maximum gravitational potential energy Maximum kinetic energy Minimum gravitational potential energy

2. 45 degrees

The basic motion equation x=Voxt Range of Trajector)y can be used to find the range By symmetry, the total time of flight is equal to twice the time at the peak: range2t This gives peak = 26sin θ cos θ 9 The acceleration all points of the Calculation 9 using the trig identity: 0912 - R ange=R =

3.FALSE. The work against gravity is same and is equal to mgh. where h is the height of the truck and m is the mass of furniture

Answer 4

u=0 Fr= max FT = min Us = max KE = 0 Fr = max KE-0 FT min θ max θ=0 u=max U,=min Fr=0 KE-max FT max 0 KE max

45 degrees goes the farthest. This is due to the nature of right triangles. Additionally, from the equation for the range :

u" sin 2θ

We can see that the Range will be maximum when the value of $\sin 2 \theta$ is the highest (i.e, when it is equal to 1). Clearly, $2 \theta$ has to be 90 degrees. That is to say, $\theta$ is 45 degrees.

A) TRUE

B) 45