Answer: d. 5 m/s^2
Explanation:
Acceleration is the change in velocity in a given time.
a = (30-20)/2 = 5
Answer:
A. kinetic energy
B. angular velocity
E. angular position
Explanation:
The quantities that cannot be constant if a constant net torque is exerted on an objecta are:
A. Kinetic energy. If a torque is applied, the linear or angular speed will be changing at a rate proportional to the torque, so the kinetic energy will change too.
B. Angular velocity. It will change at a rate equal to the torque.
C. Angular position. If the angular velocity changes, the angular position will change.
Answer:
F=5833.3 N N
Explanation:
Newton's second law applied to the car
F= m*a Formula (1)
F: Force in Newtons (N)
m : mass in kg
a: acceleration ( m/s²)
kinematics car
vf= v₀ + a*t Formula (2)
vf : final velocity (m/s)
v₀ : final velocity (m/s)
a : acceleration ( m/s²)
t : time t
Equivalences
1 km= 1000m
1 h = 3600 s
Data
m= 1000kg
v₀ = 90 km/h = 90*1000/3600 m/s = 25 m/s
vf= 0
t= 6 s
Problem Development
We calculate the acceleration replacing the data in the formula (2) :
0 = 25 + a*6
a= -25/6 = -4.16 m/s² ( The negative sign indicates that the car is braking)
We calculate the force is required to stop the car replacing the data in the formula (1)
-F = 1400 kg*(-4.16 m/s²)
F=5833.3 N
Answer:
The inter-molecular forces holding non-polar compounds together is low compare to that of polar compounds. Therefore, it will take less energy to break the bond for non-polar compounds and vice versa. That is why polar compounds have higher melting points than non-polar compounds.
Explanation:
Acceleration = change in velocity/time
By F = ma,
6 = 33 x change in velocity / 9
change in velocity = +1.636 m/s
