Answer:
Explanation:
For this case we can use the second law of Newton given by:
The friction force on this case is defined as :
Where N represent the normal force, the kinetic friction coeffient and a the acceleration.
For this case we can assume that the only force is the friction force and we have:
Replacing the friction force we got:
We can cancel the mass and we have:
And now we can use the following kinematic formula in order to find the distance travelled:
Assuming the final velocity is 0 we can find the distance like this:
Answer:
<h2> 27m/s</h2>
Explanation:
Given data
initital velocity u=15m/s
deceleration a=3m/s^2
time t= 4 seconds
final velocity v= ?
Applying the expression
v=u+at------1
substituting our data into the expression we have
v=15+3*4
v=15+12
v=27m/s
The velocity after 4 seconds is 27m/s
Answer:+1.25 m/s
Explanation:
Given
mass of ice skater M=70 kg
mass of ball m=10 kg
the initial velocity of the ball
Conserving linear momentum
Therefore the velocity of the person holding the ball is 1.25 m/s
This collision represents the perfectly inelastic collision where particles stick together after the collision.
Answer:
The sound level will be 1.870 dB louder.
Explanation:
Given that,
Power = 130 W
Power = 200 W
We need to calculate the sound level
Using formula of sound level
For one amplifier,
...(I)
For other amplifier,
...(II)
For difference in dB levels
Hence, The sound level will be 1.870 dB louder.
Answer:
θ = 8.50°
To the nearest angle
θ = 9.0°
the golfer must hit the ball at angle 9° so that it travels 120 feet.
Explanation:
The range of a projectile is the horizontal distance covered by a projectile, which can be written as;
r = (u^2× sin2θ)/g
Where;
r = range
u = initial speed
θ = angle from horizontal
g = acceleration due to gravity
Solving for θ,
sin2θ = rg/u^2
θ = 1/2 × sin⁻¹(rg/u^2) ....1
Given;
r = 120 ft
u = 115 ft/s
g = 9.81m/s = 32.2 ft/s
Substituting the values into the equation 1;
θ = 1/2 × sin⁻¹(120×32.2/115^2)
θ = 1/2 × sin⁻¹(0.29217)
θ = 1/2 × 17.00
θ = 8.50°
To the nearest angle
θ = 9.0°