2. A stone is thrown horizontally at a speed of 6.0 m/s from the top of a cliff 78.4 m high.

Starting from rest, a 2-m-long pendulum swings from an angleof

Andrews [41]

Answer:

D.) 1m/s

Explanation:

Assume the initial angle of the swing is 12.8 degree with respect to the vertical. We can calculate the vertical distance from this initial point to the lowest point by first calculate the vertical distance from this point the the pivot point:

$L_1 = L*cos(12.8) = 2*0.975 = 1.95 m$

where L is the pendulum length

The vertical distance from the lowest point to the pivot point $L_2$ is the pendulum length 2m

this means the vertical distance from this initial point to the lowest point is simply:

$L_3 = L_2 - L_1 = 2 - 1.95 = 0.05 m$

As the pendulum travel (vertically) from the initial point to the bottom point, its potential energy is converted to kinetic energy:

$E_p = E_k$

$mgh = mv^2/2$

where m is the mass of the pendulum, g = 10 m/s2 is the constant gravitational acceleration, h = 0.05 is the vertical it travels, v is the pendulum velocity at the bottom, which we are trying to solve for.

The m on both sides of the equation cancel out

$v^2 = 2gh = 2*10*0.05 = 1$

$v = \sqrt{1} = 1 m/s$

so D is the correct answer

5 0

2 years ago

Something that might happen because of global warming is: __________. *

gogolik [260]

Answer:

melting polar icecaps seems the best, hopes this helps!

6 0

2 years ago

Thomas Newcomen was the first to produce a working steam engine. Why is the work of James Watt more widely known than the work o

LenaWriter [7]

Answer:

The steam engine of James watt is more efficient than Newcomen ans more suitable for the industrial revolution.

Explanation:

James Watt is more widely know for working steam engine because Watt has created better engine which is suitable for the industrial revolution. The steam engine of James watt is more efficient than Newcomen. Watt developed the condensing arrangement by using piston which lessen the initial pressure leading to effectively worked than Newcomen's

4 0

2 years ago

Can a body have zero velocity and finite acceleration?Explain

sergejj [24]

Answer:

Kinda? Depends what the question is fully asking

Explanation:

Acceleration is a change in velocity. So I guess if the velocity of something is -2 m/s and its positively accelerating at a value of +1 m/s, then that means every second its velocity changes by +1m/s.

So that -2 m/s thing after one second will be going -1 m/s.

After another second it'll be going 0 m/s.

After another itll be going +1 m/s and so on.

So at one point for a brief moment, it can have an acceleration but be at 0 m/s velocity.

5 0

3 years ago

1. When the mass of the ice added to the cup increases, the amount of thermal energy needed to change the temperature of the ice

Paha777 [63]

1. When the mass of the ice added to the cup increases, the amount of thermal energy needed to change the temperature of the ice decreases or increases

2. When the students measure the temperature of the water in the cups during the investigation, what is it the students are measuring?