Answer:
Given:
mass of the ball m = 0.144 kg
velocity v = 38 m/s
now, change in momentum
P = m v- ( - mv)
= 2 mv
=2 x (0.144) x (38)
= 10.944 kg-m/s
Impulse J= F. Δt
change in momentum is equal to impulse
J = 10.944 kg-m/s
we know force is equal to change in momentum per unit time
F = 13.68 x 10³ N
F = 13.68 kN
OK. Thank you. That's an impulse of 200 Newton-sec to the left,
telling us that the cart's leftward momentum increases by 200 kg-m/s
(or its rightward momentum decreases by that amount).
Did you have a question to ask ?
A. The fly's velocity to the ground is less than the car's velocity to the ground.
Answer:
P = 25299.75 watts
Since 80km/h is the average speed of 92km/h and 68km/h, the power (in watts) is needed to keep the car traveling at a constant 80 km/h is P = 25299.75 watts
Explanation:
Given;
Mass of car m = 1280kg
initial speed v1 = 92km/h = 92×1000/3600 m/s= 25.56m/s
Final speed v2 = 68km/h = 68×1000/3600 m/s= 18.89m/s
time taken t = 7.5s
Change in the kinetic energy of the car within that period;
∆K.E = 1/2 ×mv1^2 - 1/2 × mv2^2
∆K.E = 0.5m(v1^2 -v2^2)
Substituting the values, we have;
∆K.E = 0.5×1280(25.56^2 - 18.89^2)
∆K.E = 189748.16J
Power used during this Change;
Power P = ∆K.E/t
Substituting the values;
P = 189748.16/7.5
P = 25299.75 watts
Since 80km/h is the average speed of 92km/h and 68km/h, the power (in watts) is needed to keep the car traveling at a constant 80 km/h is P = 25299.75 watts
The mass of the seashell suspended by the two strands of spider silk is 0.28 kg.
The given parameters:
- <em>Tension on each strand of silk, T = 1.42 N</em>
- <em>Angle of inclination of each strand, θ = 75⁰</em>
The mass of the seashell at equilibrium is calculated by applying Newton's second law of motion;
where;
- W is the weight of the seashell
The weight of the seashell is calculated as;
The mass of the seashell is calculated as follows;
Thus, the mass of the seashell suspended by the two strands of spider silk is 0.28 kg.
Learn more about equilibrium forces here: brainly.com/question/8045102
