Answer: Change in ball's momentum is 1.5 kg-m/s.
Explanation: It is given that,
Mass of the ball, m = 0.15 kg
Speed before the impact, u = 6.5 m/s
Speed after the impact, v = -3.5 m/s (as it will rebound)
We need to find the change in the magnitude of the ball's momentum. It is given by :
So, the change in the ball's momentum is 1.5 kg-m/s. Hence, this is the required solution.
Read more on Brainly.com - brainly.com/question/12946012#readmore
Answer:
35°C
Explanation:
q = mCΔT
2130 J = (0.200 kg) (710 J/kg/°C) (T − 20.0°C)
T = 35°C
Answer:

Explanation:
Given:
Initial velocity of the vehicle, 
distance between the car and the tree, 
time taken to respond to the situation, 
acceleration of the car after braking, 
Using equation of motion:
..............(1)
where:
final velocity of the car when it hits the tree
initial velocity of the car when the tree falls
acceleration after the brakes are applied
distance between the tree and the car after the brakes are applied.

Now for this situation the eq. (1) becomes:
(negative sign is for the deceleration after the brake is applied to the car.)
Answer:
Mass of bike = 38 kg.
Explanation:
Kinetic energy is given by the expression,
, where m is the mass and v is the velocity.
Here speed of child riding bike = 6 m/s
Mass of child = 30 kg
Total kinetic energy = 1224 J
Let the mass of bike be, m kg
So, total mass of child and bike = (m + 30) kg
Substituting,

So, mass of bike = 38 kg.
Answer:
3. none of these
Explanation:
The rotational kinetic energy of an object is given by:

where
I is the moment of inertia
is the angular speed
In this problem, we have two objects rotating, so the total rotational kinetic energy will be the sum of the rotational energies of each object.
For disk 1:

For disk 2:

so the total energy is

So, none of the options is correct.