A ball is thrown directly upwards. Is there a point of trajectory where the ball has zero acceleration

The density of a substance equals its mass

True [87]

Answer:

The answer is the mass of d

8 0

3 years ago

Kristen, a 3-year-old, enjoys taking baths and is always willing to get into the bathtub. Kristen hates to have her fingernails

SIZIF [17.4K]

Answer:

Explanation:

The law of effect given by Edward Thorndike explains the behavior of child given in the problem . The effect which gives pleasure and satisfying effect are likely to be learnt easily and the effect which creates bad taste are likely to be forgotten easily . actions producing feel good effect are likely to be repeated in future .

3 0

4 years ago

A wheel of diameter 40.0 cm starts from rest and rotates with a constant angular acceleration of 3.00 rad/s^2. At the instant th

xxMikexx [17]

Answer:

ac= 15.07 m/s²

Explanation:

The Wheel rotates with a constant angular acceleration.:

Centripetal acceleration is calculated as follows:

ac =ω² *R Formula (1)

ac =v² / R Formula (2)

Kinematics of the wheel

We apply the equations of circular motion uniformly accelerated :

ωf²= ω₀² + 2αθ Formula (3)

v = ω* R Formula (4)

Where:

θ : angle that the wheel has rotated in a given time interval (rad)

α : angular acceleration (rad/s²)

ω₀ : initial angular speed ( rad/s)

ωf : final angular speed ( rad/s)

v: tangential velocity of a point on the rim ( m/s)

R : radius of wheel (m)

ac: centripetal acceleration, (m/s²)

Data:

D = 40.0 cm : diameter of the wheel

R = D/2= 40.0 cm/ 2 = 20 cm = 0.2m

α = 3.00 rad/s^2

ω₀ = 0

n = 2 revolutions : number of revolutions

θ =2πn (rad) = 2π*2 (rad) = 4π rad

Calculate of the ωf

We replace data in the formula (3)

ωf²= ω₀² + 2αθ

ωf²= 0 + 2(3)(4π)

ωf²= 24π

$w_{f} = \sqrt{24\pi }$

ωf = 8.68 rad/s

Calculate of the v

We replace data in the formula (4)

v = ω*R

v = (8.68)*(0.2)

v = 1.736 m/s

Calculate of the ac

We replace data in the formula (1)

ac = ( ω)²*(R)

ac = (8.68)²*(0.2)

ac = 15.07 m/s²

We replace data in the formula (2)

ac = v²/ R

ac = ( 1.736 )²/(0.2)

ac = 15.07 m/s²

7 0

4 years ago

What energy comes from swinging a bat

hjlf

Answer:

Kinetic Energy

Explanation:

The potential energy is being converted into kinetic energy. The hitter has struck the ball transferring the kinetic energy from the swinging bat to the ball.

8 0

3 years ago

A 2.00-kg block is pushed against a spring with negligible mass and force constant k = 400 N/m, compressing it 0.220 m. When the

marin [14]

Answer:

0.82052 m

Explanation:

potential energy of spring = kinetic energy

=> 0.5kx^2 = 0.5mv^2

=> $v=\sqrt{\frac{kx^2}{m} }$

$v=\sqrt{\frac{400\times 0.220^2}{2} }$

v= 3.11127 m/s

angle = 37°

thus height = distance×sin(37) = D×0.60182

Also,

m×g×h = 0.5×m×v^2

=> 2×9.8×D×0.60182 = 0.5×2×3.11127×3.11127

=> D = 0.82052 m

4 0

3 years ago