Find out the speed of the car from home to school in meters per second.

1.2

Alika [10]

Answer:

B

Explanation:

Because it has to increase

3 0

3 years ago

Read 2 more answers

What do the length of the cord and gravity determine for a pendulum?

rusak2 [61]

Answer: C

Period/ Period of the pendulum.

Content:

Simple pendulum is a small diameter bob which is suspended from light cord or string. The string is strong enough to stretch.

Pendulums are quiet common in use such as clocks, swings etc.,

From the simple pendulum we can find conditions under which it performs simple harmonic motion and we can also derive the expressions for Period of pendulum, frequency etc.

Period of a pendulum/Time period is given by the following expression

 T =2π.√(L/g) seconds 

 T = period of pendulum in seconds

L = Length of the string/cord in meters

g = gravitational force in m/s² ( g = 9.8 m/s² )

Period of pendulum is independent on mass of the bob.

So, The relation between length of the cord and gravity is used to determine the period of pendulum

4 0

3 years ago

Change in Energy Quick Check

nika2105 [10]

Answer:

The force of gravity on the object decreases. (FALSE)

The potential energy of the object decreases. (TRUE)

The acceleration due to gravity decreases. (FALSE)

The kinetic energy of the object decrease (FALSE)

Explanation:

FORCE OF GRAVITY:

Force of gravity on the object is the weight of object, which depends upon the mass and value of acceleration due to gravity (W = mg). Since, the value mass is constant on Earth and acceleration due to gravity is also constant on earth.

Therefore, force of gravity remains same on the object. The statement is false.

POTENTIAL ENERGY:

Potential energy of object depends upon the mass, value of acceleration due to gravity, and change in height of object (P.E = mgΔh). Since, the value mass is constant on Earth and acceleration due to gravity increases as the object moves towards the surface of earth. But, the height of object is decreasing.

Therefore, potential energy of object decreases. The statement is true.

ACCELERATION DUE TO GRAVITY:

Acceleration due to gravity depends upon the altitude (gh = g[1 - 2h/Re]). Since, the height of object is decreasing.

Therefore, acceleration due to gravity increases. The statement is false.

But, this change is not significant.

KINETIC ENERGY:

Kinetic Energy of object, which depends upon the mass and velocity of the object (K.E = mv²/2). Since, the value mass is constant on Earth and velocity increases as the object moves towards the surface of earth.

Therefore, kinetic energy of the object also increases. The statement is false.

4 0

3 years ago

A skydiver, with a mass of 60 kg is falling at a velocity of 30 m/s. Calculate his kinetic energy.

ddd [48]

Answer:

27000 J

Explanation:

4 0

3 years ago

The graph in Figure 4.15 shows the position and time for two runners in a race. Who has the faster speed, Robin or Joel? Explain

Burka [1]

Answer:

Joel has the faster speed.

Explanation:

Joel has a steeper slope on the graph. The steeper a slope is, the faster speed will be. Therefore, Joel's slope is steeper which increases overall speed.

4 0

3 years ago