Answer:
Explanation:
Question is incomplete
Assuming the question you have asked is
You are driving home from school steadily at 95 km/h for 180 km. It then begins to rain and you slow to 65 km/h. You arrive home after driving 4.5 h.
given,
speed of 95 km/h for 180 km
due to rain
speed is reduced to 65 km/h
distance traveled in 4.5 hour
time taken to travel 180 km
d = s x t

t = 1.9 hr
distance traveled in time, t' = 4.5-1.9 = 2.6 hr
Speed of vehicle = 65 Km/h
d' = s x t'
d' = 65 x 2.6
d'= 169 Km
total distance your hometown from school
D = d + d'
D = 180 + 169
D = 349 Km
Answer:
(a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Explanation:
Given that,
Acceleration = a
mass = m
spring constant = k
(a). We need to calculate the spring compressed
Using balance equation

....(I)
The spring compressed is
.
(b). If the compression is 2.5 times larger than it is when the mass sits in a still elevator,
The compression is given by

Here, acceleration is zero
So, 
We need to calculate the acceleration
Put the value of x in equation (I)




Hence, (a). The spring compressed is
.
(b). The acceleration is 1.5 g.
Answer:
0m/s²
Explanation:
Given parameters:
Initial velocity of the boat = 8m/s
Final velocity = 8m/s
Time taken = 4s
Unknown:
Acceleration of the boat = ?
Solution:
Acceleration is the rate of change of velocity with time.
It is mathematically expressed as;
A =
A is the acceleration
v is the final velocity
u is the initial velocity
t is the time taken
Insert the parameters and solve;
A =
= 0m/s²
True.
I think that’s the answer.
Answer:
η = 40 %
Explanation:
Given that
Qa ,Heat addition= 1000 J
Qr,Heat rejection= 600 J
Work done ,W= 400 J
We know that ,efficiency of a engine given as

Now by putting the values in the above equation ,then we get

η = 0.4
The efficiency in percentage is given as
η = 0.4 x 100 %
η = 40 %
Therefore the answer will be 40%.